My DH & I have been married for 6 years. He was married to his Ex for 20+ years, they have a daughter- now aged 19 3/4 yrs. I have 2 sons (9 & 11) from a prior marriage- their BD passed away when my oldest was 3yrs old.

My SD lived with her BM after divorce, moved in with us when she was 15 yrs old- BM had zero contact with her for nearly a year (lived a whopping 35 minutes away)- Things were fine as wine until... (you're already guessing, right?) BM came back into SD's life, DH & I encouraged her to have regular contact w/ her mom, etc. Until at age 17 she ran away from home- She went to BM's for a regular weekend visit and called to say she wasn't coming hom- no further explanation. Keep in mind that, upon divorce, visitation/custody was "frequent & liberal" which means nothing. After DH & I started our relationship and BM jerked DH around on "his" weekends, we hired an atty., went to court and had an actual custody agreement. When SD wanted to move in with us, we went back to court, changed custody, etc.

Well, fast forward 2+ years and SD again begins to contact her Dad- He had made regular attemtps during those 2+ years, calling, sending cards, etc. Never received any replies.

Last Year, I talked to DH about SD moving in with us as she had hinted around. Upon her graduation from HighSchool she did not continue onto college, just worked PT at a grocery store.

Fast forward again--- she moved in with us, we got her enrolled in college, she wound up losing her job, we told her she didn't need to pay anything, just concentrate on her school.
Fast forward 1 semester and we found out that she basically had quit attending classes- Faked us out to believe she was going- blew her entire semester, failed everything.
When this happened, we took swift action. Talked & talked, decided to clamp down with bedtimes, weekly updates on her classes, etc.
During the months since then, things have gone down hill. I've gone home several times to find her sleeping at 12:30 when she's required to be up by 9:30...
DH & I have talked and talked and instituted more rules, monitoring, etc.
After giving her an ultimatium which DH & I were in agreement on- "Walk straight, follow the minimal rules we have or you'll be asked to leave" . . . I found her once again sleeping after she had texted me twice (per our requirements) to verify she was up at 9:30 and 10:30 - Basically she woke at 9:30, texted me, woke at 10:30, texted me and when I walked in the house at 10:45, she was in her dark room with all the lights out, had not been up (BUT she wasn't sleeping- she was just laying there with her eyes closed!!!).
I talked to DH about her leaving and he basically hemmed and hawed his way around it which left me infuriated & at the end of my rope.

So --- here's what I've don:

Told DH that:

I'm done working on helping, guiding, "fixing" her- my focus will now shift to the family as a whole.
I'm no longer willing to let her change the atmosphere in our house to one of chaos, to that end if he & she are engaged in some conflict, the boys & I will get in the car and leave- Hopefully, when we return in an hour or so, they're done with their conflict.
I'm stepping out of the duties of "managing" SD. He'll now be responsible for checking in on her, keeping on top of her class work, etc.
I'm going to look to DH to hold her accountable for chores, bedtimes, etc. So If I come home and her chore isn't done- I'll ask him to do it or see that it's done.

I was very clear with him and told him I need peace for myself and the boys. I'm not trying to punish him but I'm done with the conflict in my life.

I'd ultimately like my SD to leave our house. She's only bringing conflict in and everything we've tried to do to help her has been for nothing. - she's talked about joining the military and I honestly think that would be the best thing for her- she's completely unmotivated- with zero ambition and a serious case of "the grass is greener" syndrome!

I'm 100% prepared to follow through and anticipate having to leave my home with the boys a few times a week when they're having a disagreement with each other.

I'm also prepared to put up with this for about another 5 or 6 weeks. If he hasn't had her leave at that point I'll have to make my next move which would consist of another conversation with DH telling him that, since the situation hasn't improved I feel like it's best for me and the boys to leave for a week or two so he and SD can really work on their problems.

I feel like this is the only thing that will make my DH realize just how much I've been doing on a daily basis for SD and it will bring a harsh light on how much chaos she's causing.

Can anyone give me feedback if you've taken similar steps?- If so how long did the situation continue before a meaningful change occured?