I came home to a note saying I was the problem and that he had taken an apartment. He said he "loves" me, but can't abide my anger over his teenage daughter.
Seems to me, this is the key. Whether you agree or not, his perception is that his issues with his D were worsened, or his life made more difficult, by your anger over her.
Now, I don't doubt that step-parenting under those conditions is difficult. She may have been the teenager from hell for all I know. But she is the child and you are the adults. She didn't ask for the disruption caused in her life by the adults in it. Your H probably feels guilt over his role in her dysfunction.
The bottom line is, he did what he felt was right by choosing to protect his daughter. And he may simply have been overwhelmed, trying to deal with her AND deal with your anger. Parenting unruly teens is hard enough when your spouse has your back.
So, where am I going with all this? I think, if you want him back, you need to VALIDATE what he experienced. Admit that your approach was not helpful to him in that stressful situation. Tell him you don't want to be an obstacle between him and his D. Tell him you miss him terribly and would hope that the two of you could perhaps still see each other, just not live in the same house? I would try a little humility, and understanding. He's been placed in a terrible position between the two of you.
