When she walks in at 3:00 a.m., what does she see at home? Are the outside lights off and everything locked up or does she see the porch light still glowing? Is everything inside dark? Are you sound asleep or at least acting as if your are, or are you waiting up for her?
You need to live as if she is no longer a part of your life. Go forward each day making plans with your children and just ignore her presence in the house. Of course, if she directs a question to you, you answer without any emotion as if she was someone you met crossing the street.
Take care of business and the needs of the children. Take care of yourself. Tune her out and do not try to have any lovie-dovie times. She has made her feelings about that....very plain, so no more pursuing.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!