Ask him why he doesn't love her enough to help her grow up. His job, as her father, is to help her become a self-sufficient, decent and capable adult - that doesn't happen by sitting on your arse and letting life unroll. At present, you are doing the parenting that he is too darn lazy to do.

If he doesn't step up and soon, your life is going to be a living hell.

I can't believe his baby mom would want her daughter to grow up like this.  I'm sure she had hopes of raising a strong independent daughter.  Have you asked him what hopes she had for her daughter when she was born?  You need to take him back to the beginning of her life and tap into those memories and hopes.  Losing a parent at a young age sucks but it should not define your future.  Resilience is the word you need to use.  SD needs to be brought up to make her mother proud, going this route of indulging her out of pity will only set her up for failure.  
 

It will also set you up for a divorce.  

Would HE go to counseling? Or take parenting classes? HE is the problem, and the daughter's behavior is the consequence of poor parenting.

I also felt like the only responsible one in the household -- any my skid was an adult at the time. It is lonely. And frustrating. And sort of unbelievable, like what alternate universe did I enter and how did I get here? I reached a point over this and several other issues that DH was either going to be a responsible partner or I'd be out.  I hope you don't get to that point.

Think about what YOU need to be happy. Then work with your DH to make a plan to get there so that you are not the sole parent. If he won't, then you have another kind of answer and he's tellin you that his lazy "laid back" comfort is more important anything you need.

Just don't build your life on the fantasy of what "should be."

Your SO is definitely the problem.. his wife.. has been dead.. what.. less than 2 years at this point?  I think at first you must have seen him and his daughter needed the help.. you could fix it.. make it better... that his lack of motivation etc.. and coddling was due to his EX's illness.. perhaps he was just a crap husband and crap parent all along?  It's not like you can ask his EX right?  5 months is an incredibly short time before marriage.. you could not have possibly truly known him beyond the image he projected for you.  

Your expectations may be reasonable.. but if she is a child with no foundation.. you can't start buiding from the third floor up right?  and if her father doesn't want it... it wil be an endless source of conflict.. honestly.. without a lot of counseling to explore this.. i'm not sure it's worth staying.

You aren't failing as a SM, you DH is failing as a father.

I'd look at his behaviours and see if he is gas lighting you in other ways.  It sounds like you've been love bombed and are now seeing his real personality.

Your husband is the problem here. Frankly, it sounds like he didn't want to do the heavy lifting of raising his daughter and running a household, so he quickly found you to do that for him. I would step way back  and see if he then stepped up. What are YOU getting out of these relationships?

My mother had a stroke when i was 21, i was still growing up and drs told us mum was gonna die (all the signs were there), she lived another 9 years. 
 
life went on, i didn't get to use mums stroke or death to not do chores, not cook, clean or go to work etc. yes i was mourning and overwhelmed but life went on. 
your husband is making it like his exwifes death will make his daughter cry if she has to do minor chores that take a few mins a day- that's ridiculous 

The step life trap is what this is called.

You are guven responsibility, the household maid and nanny, but with no authority.

Your DH is taking the easy way out, then twisting it on you saying you are emotional and high strung. Gaslighting at its finest.

The way its headed if your DH keeps his head up his ass is a SD being the queen, and you are the maid. 

This isnt a good marriage. Either therapy for the family or you have years, like a lifetime of feeling lonely, unheard, and sad.

You have lots to think about. 

You could somewhat disengage. Not sure big daddio would be keen on that, and then more trouble brews.

Sounds like big daddio will cater to SD and this creates the perfect storm of a nightmare for a SM. Unless he changes his parenting there is no happy outcome for you.

Blessings

Sounds like DH was trying to hide being a lazy parent, by trying to replace BM with you. It's so much easier for him to pawn off literally everything to you, instead of DH being accountable. Especially in 5 months... I think you got duped. If DH knew all you wanted was "to be a Mom" sounds like he sold you a great story. He gets to claim "making your dreams come true" all the while he gets to sit back and do nothing. It's not too late to realize this is NOT what you wanted. Also, SD is very young still. You are setting yourself up for YEARS of unhappiness. 

I think you've been given the ole bait n switch. You're not a failure, you're just a good person in a dysfunctional situation. This man decided to source a new wife appliance, and lovebombed you to catch you. Can you respect or trust such a person?

I also think you don't understand what your role is and is not. You're doing far too much and setting a very bad precedent. The cold truth is your H is the parent, and a lazy, overly indulgent one at that. He's creating a monster, and as bad as things are now, if you stick around just wait until that girl is twelve or so. 

Your description of your H gives off very strong narcissism vibes. You're in a bad situation, and there's nothing wrong with admitting you made a mistake marrying this man. He rushed you so you wouldn't have time to vet him properly, but now you see the dysfunction. Start putting together an exit strategy and save yourself. You're not the first woman this has happened to and you CAN move on to something healthier.

The poor dead BM's husband hooks up with and marries another woman months after she dies. Slides this new woman into the mother role letting her do all the heavy lifting of parenting. Actively undermines this new woman's efforts, using the dead BM as an excuse. Probably to make himself feel like the "amazing dad" when he "rescues" the poor child from being parented. The child suffers in that they are not raised properly. The new woman blames herself and feels like a failure, and the man gaslights her by bringing up the dead BM to silence her very valid concerns. New woman is miserable and doesn't feel like her house is her home. I bet OP has questioned herself, wondering if she is "selfish." This guy isn't honoring either of his wives. He is being selfish but probably being hailed as this amazing hero dad. We see you, OP. You are not a second class citizen of your home. Demand counseling and demand respect. 

The "missing piece" is YOU.  You've lost yourself in their drama.  DH brought you on board because of the fact that you were a strong, independant woman.  He knew that he could just sit back and let you do all of the heavy lifting because it's probably in your make up to do so.  He probably love-bombed you to ensure that you would stick around and he seemed like the perfect package.  A windower!  No ex-wife to contend with.  Luck you.  But not really!  He actually sounds like a Man-Child and a Disney Dad all rolled into one. 

The part that worries me is that you two are already in "counseling" and you've only been married a year?  I'm sorry.  I have to be brutally honest.  I'd cut my loses and get out of this marriage now, before you invest too much more of your time and energy into it.  He's not going to change.  Your SD is only going to get worse. 

You've done all that you can do here.  Time to move on....

That.... is the question.

You are not and have not failed as an SM. Your DH is the failure. He was failing as a father before his first wife passed, he is failing as a father now, and he is failing as your partner.

End it. Move on.

Save yourself countless yeas of pain.

Take a look at the opinion piece I just shared on my ST Blog and on the General Forum. About Red Flags.  Your DH, is full of them and you cannot make excuses for him or take on his failures as yours.

IMHO of course.

Time for you to steop doing anything and everything including contributing financially. Let DH parent, pay the bills, clean the house, etc, etc, etc...... You live your life and find a strong attorney to facilitate your departure so you do not waste your life and happiness on this shit show.  A shit show that is entirely the responsibility and failure of your hopefully STBXH.

"My husband would be happy if I just did all of it. If I get upset, he tells me I’m too sensitive and that I need to extend more grace because of her mother’s death. My fear is that my SD and husband will use this as a crutch for the foreseeable future. I want her past to be a source of strength rather than weakness. I was teaching her to wash her own hair (checking it at the end to make sure all soap was removed), and now he just does it for her because it’s easier."

My ex husband would ignore me, berate me, ridicule me and treat me like garbage - and when I got upset, he responded, "You're too sensitive." 

No no no and NO to this entire situation. 

I read your post and am deeply bothered by what you are going through.  I must say, I agree with the other posters:  you have been duped, he is passing off the hard parts of parenting/running the household to you and all the while, being the Disney Dad/manchild, refusing to parent/raise his daughter so he can look like "the good guy."  I feel like if you stay, the situation will deteriorate and you will be miserable beyond words. Your DH and his daughter will use the death of BM as a crutch, they already are. 

Newsflash:  You haven't failed, at anything.  DH has failed you AND his daughter - and miserably so. 

Please think long and hard about what you want for YOU.

We're here for you!  **HUGS**

being someone who lost my husband while my son was 7yrs old,, i feel this man has no idea what hes doing at the moment , especially getting married so soon,, hes simply trying to fill a void.  It took me years to really become settled again and start parenting properly again.  It takes years to figure out who you are as a person without your spouse anymore , and it sounds like he hasnt done any of this ,,,just remarried ,  unfortuneately you have filled the void for now, he will be happy for you to do everything for him.   i can understand that its extremely difficult being the partner of a widower and the 'excuses' will always be there no matter how far down the track,,,,its been 13years since my husband passed away and i still have moments where i need to use an excuse when grief smacks me in the face.  I can only give my experience of being a widow and how it was for the man that i had a relationship with after my husbands death.   there is no excuse for not teaching his child life skills    

I wouldn't let my husband act like this if it was our bio kid. Stop doing everything, just stop, let the chips fall on his head.