Meth addiction is really terrible.  I hope she breaks that addiction.

For B/M - I think you do fade into the background.  TT will likely revert to her normal crappy parenting at some point but for now trying to 'interfere' with her and B/M won't end well for you.  They will just paint you as the bad guy again.

My condolences regarding your niece.  It is heartwrenching to watch people we love destroy themselves.  

As for TT, why did your DH allow her to take his time?  He needs to highlight the COd visitation schedule and smack TT in the face with it when she pulls this crap.  DH needs to tell SD-15.5 that his time is  his time and he will make sure she gets to her events on his time. If TT undermines, go over the top on a killer dress, shoes, and full hair and makeover letting TT sit on what ever she purchased.

Fixing this takes zero tolerance for the toxic parent interfering in our side of the equation.

IMHO of course.

I think being in the background is where I am as a SM.  When they all lived here, I was in more of a "Mom" role.  I dont care, its fine with me.  They see me, not as an individual, but as Dad's support.  Incidentally, this dynamic isnt just for step-parents, I sense a similar thing with ny daughters in law where their own biomoms are #1  and I'm just in a supporting position.  

Clove, you seem to want more "family interaction".  I'm afraid youre going to be disappointed and I hate to see that.  As Munchkin gets older, she'll be more and more wrapped up in her own life and seldom look back.  Its just the way it is.

Hoping for the best for your niece, that's tough.

Even in intact families  kids grow up, go on to do their own things, move out, move far etc Your SD will be grown up soon and will be out.  So you have to adjust to your new reality. Even if she was your own DD she'd spend less and less time at home.  

Even if you had the most loving relationship with your kids or skids, they might attend college on the other side of the country and then marry someone even further out so you might only see them for holidays and vacations. 

I think it's important that you and your DH have things in common and strong relationship so you won't rely on kids to maintain sense of home and family. Have a full life so it doesn't feel like a hole in your heart every time skids are out and about or with the other parent.

as about what DH could do with SD, he is an adult and could figure it out or not figure it out. You can't do much about it. 
 

Pictures would be nice. But that's just one event. I don't have pics of every event of my own DD. It's fine. That's not uncommon especially in divorced situations. You can have her pics of other events. It's just pictures. Don't let it bother you 

yeah I don't know if you should assume that SD only does things with mom because she thinks that's what mom wants. It's very possible that SD wants time with her mom, it's not abnormal. Even if she is the most awful person, she is her mom. I don't see regular things like getting ready for an event and doing girly things as enmeshment. I think what she does with her mom is fairly normal (even if you hate BM) 

oh no sorry about your niece. How sad. I hope she pulls through 

My bride and I certainly had some adjustments when we became empty nesters. Though we did it in two phases.  First was when we dropped him off at Military School for his Jr. and Sr. years of HS.  Then after we finally got him graduated, we dropped him off 10mos later at MEPs to start his USAF career 4mos before he turned 19.  It is hard to believe that the tow headed toddler who invaded my life when i met his mom will be 30 this year.

With boys there is not the same investment as there is in the whole becoming a woman thing. Prom is either a run to the Tux store to rent one, or buying a suit.  Neither are nearly as special as the whole Prom dress, salon thing proces.  At least apparently they aren't.  I would not know. I have never been a girl or had a girl to raise.

I am sorry that this is weighing so heavily on you Clove.  

Does your DH ever plan anything with SD15?  Does he talk to her about her life?  Ask her about her friends?  That is not something you can fix, that is something he needs to do on his own.  

I understand how hard it is to watch the toxic waste of a mother suddenly decide she wants to be a mother and the kid eats it up.   You can ask her about the dance, ask to see photos, there is nothing wrong with that.  Showing a general interest in SD15 is good, but it doesn’t mean you need to start feeling like you have to “parent” her.  Think of it along the lines of a co-worker.  You ask them how their day is, you engage in small talk, but you don’t start telling them how to write up a report or that they need to tidy up their office. 

I'm sorry about your niece, I really hope her want to live is stronger than her desire for the meth.

Getting involved in the big sister organization? I think you would be awesome and you might find it a good fit for you. When I was young I had a "big sis" and it really did make an impact on me. 
 

 So many of your posts resonate with me because I know it's what I would have faced had DH and I become involved while he had kids at home. I, like you have a big heart and the first few years we were married I really thought things would be different than they are. They (the adult skids) pay a lot of lip service to me and DH and how "ammaaaaaazing" I am and what wonderful things I've brought into their lives. Apparently the ex wife got that memo too, since I was even told in the "family" group chats that included her and even she would wax poetic about how wonderful I've been for allllllll of them..... yea uhmm what?
 

I began to realize I was the only one investing in my relationship with these people, they were more than happy to soak up whatever goodwill (and event planning and execution I took on) but guess what was reciprocated? Yep nothing ..... other than fancy words and compliments.  When the OSS (45) and OSD (43) began busting their dads chops because he (at my insistence) finally put some boundaries around their mother continually being included in every single family event they put together and us not including her in ours plus us feeling like we were invited last minute almost as an oversight, they lost their minds over the "pettiness" of it  and I've been detaching ever since. I don't have any real advice other than only 2-3 more years and hopefully she will be out of your home and you'll have at least some peace, although these types never seem to really calm down. At least in my experience.