Nancy, I'm so very sorry to hear she relapsed, but you're absolutely right about it taking several times for many. Not an easy thing to deal with as a parent though, as I know all too well.
The other house's rules about not dating aren't uncommon. Most AA and substance abuse programs encourage the addicts to not get into a relationship for a year, as they need time to work on just themselves. That being said, it's definitely hard to feel so alone, at times.
I'm glad J is still at the sober house and is hopefully back on track. The fact that she's still there is definitely a good thing. One little misstep doesn't mean she can't start moving forward again.
Hugs to you and hope that she continues with the program.
Deb