Yoir feelings are completely normal. If anyone should have to be the maid going behind them and cleaning up it should be their dad. If he has to do it i bet he will up the discipline. Don't enable them. Either they pick up behind themselves and do basic hygiene without being hounded or their dad makes them. 

You'll hear from MANY people who feel as you do.  It is not easy raising someone else's children, I know, I raised 3 of them.  The good news is your partner sounds supportive.

I'd recommend sitting down (regularly) with your partner to sync up.  For starters, he's the one who should be disciplining the kids, not you.  Ideally, you two would decide on the kids' behavior standards, hygiene and chores and he should be the one enforcing it all.

Know that you are NOT a monster and also know you shouldn't feel like a maid in your home.  Again, your partner should be enforcing respect for you and help with the work caused by 2 extra people in your house.

BM: of course you are angry with her.  You didn't say what led to this custody change, but is she pulling her weight?  Does she see the kids on a regular basis?  Does she pay child support,?  My DH let our BM off the hook in many ways, it was tough.  I was so wound up in my own feelings I did not realize for a long time that the kids felt abandoned.  Your SKs might, too.

Read around on this site and you'll learn much about neglectful bio parents, stressed stepparents, lazy Disney Dads and so much more.  You've come to the right place.  Good luck!

Welcome to the site, AJC1996!

 It’s not surprising that you are having difficulty in your new role as stepmother since your husband seems to believe that raising children is a woman’s job. If the responsibility for the boys continues to be handed off to you, a woman who is unrelated to them, you will soon build up a resentment that will kill your marriage.

Hon, the boys are NOT your children! They are your husband’s and the responsibility for disciplining them, picking up after them and ensuring that they observe basic hygiene is HIS! Having suddenly found yourself landed with someone else’s children in your home, you must begin as you aim to continue. If you make the mistake of assuming the grunt work of childcare and letting your husband off the hook for raising his own, biological kids, you will not only build huge resentment but will be stuck with the job ad infinitum.

You have written that you love the boys which is surprising since they are not yours and they sound both uncooperative and disobedient. No sensible woman would be capable of loving such children unless, of course, she had given birth to them. Hon, you are a long way from being ‘a monster’. Any woman would feel the same, under these circumstances.Please stick with the site and do some reading, It's clear that you need us!

Welcome to step hell!

Same shit you're dealing with is THE EXACT same stuff I'm dealing with now. 
 

Except this dude thinks because his kids are here every weekend vs every day that they don't have to do any chores, don't have to follow any rules, anc stay up all damn night, can raid the fridge any time time of day or night, can shout and yell all across the house

It's so annoying that I'm about to break it off and leave 

If these bio parents understood that if their kids had some home training, followed our reasonable rules, enforced/back us up if we have to enforce, etc we'd be more welcoming of their spawns and more willing to stay with them

In our case, full time was, to my shock, easier than weekends cuz everyone was under the same roof all the time without the back-and-forth transition.

But, I was thinking back to my own childhood when I visited beloved gparent's for a few weeks each summer.  I did things I couldn't have done at home: raided the frig for snacks all the time, stayed up til all hours, watched tv endlessly, received plenty of "shopping money" etc.   It seemed natural and it also seemed natural when I went home to a more regulated life.

Perhaps your partner and the kids are still in "weekend" mode and haven't made the switch yet.

Welcome! Good news is at the ages they are they are able to understand a conversation your SO can have with them to help the discipline be respected in your home. 
From personal experience my DH sat down both SS and SD and told them Floral does not have to lift a finger for them as they are not my children. I don't have to take them to school, cook or clean for them, I could easily ignore them completely when they are here and leave it on them how to get themselves to school and find clean clothes to wear when DH isn't home. But, because I am a nice, caring, loving person and mother to our DD2 and baby on the way (Thanks DH <3) I help HIM and THEM out by taking them to school, cooking, washing, cleaning ect and ensuring they live in a safe, clean and happy home. All he asks in return from them is to listen and respect me if I ask them to do something as whatever I ask them, is an extension from him. He also explained to them Any rules they have to go by are the rules we set together and he enforces it on them as they are HIS children and I support him as we are a team. 
Ever since that talk they have been loads better in our home with being respectful and keeping up their hygiene and rooms clean. Hopefully your SO can communicate with them on that front. My actions speak louder than their HCBM words, and they know I'm a nice and caring person just how I help them look after their home when they are here, as they help me by respecting me when I tell them to do something now. 
You need your DH support and him to enforce the consequences for this to work though, otherwise if they see their dad doesn't act on it then why do they have to listen to you sort of thing. 

Good stuff, Floral!

Where is your partner? Why isn't he parenting, cleaning, disciplining, and being an adult?

Based on the content of your original post, you have a monster problem for sure. The invisible supposed partner who has sucked you into his failed family nightmare. You... have an Incubus. Taking your life energy for his own benefit.

At least based on the infirmation provided.

You don't sound like a monster at all, but your partner sounds like a crappy parent.  Why isn't HE disciplining his children, cleaning up their messes and teaching them basic life skills, like hygiene and cleaning up after themselves?  This situation doesn't sound sustainable,  because eventually you will resent him and his children as you do so much of the work (and likely get little appreciation). Push a lot more of the work of parenting HIS children into HIM.

One thing you will see from this site. That a lot of your feelings are normal..That. Society, The movies, Tv. You frees and family all have different ideers on how you should fee ,You had no say in this kids being born.  That your SO is guilty for being divorced and breaking up. "Happy Family". You have no emotions for these kids.  As when kids do well, SO feels like he was responsible for his kids doing well 

So read the blogs,  thy to understand SL.   The kids should have a bed time, so you and DH have Adult time.  It may suck for the kids.  But everyone must give for this relationship to work..  This everyone must give is a big thing..You are giving. Taking of kids that are not yours, kids must give  too. DH must give.

And be sure to read up on all the posts.  For starters here is a variation on an old tenet:  you can't care more than the biological parent https://blendedfamilyfrappe.com/disengaging-essay