Separated

my wife and i recently got separated. he has been treated multiple times for depression and mental instability being diagnosed bi-polar and borderline personality dissorder. we've hit a few bumps on the road, and one morning, she woke up and said she wanted out. she was tired of the mental abuse. this hit me hard in the gut. abuse? i love this woman. the mother of my child. she recently has been admitted twice to a mental therapy clinic. once, after a emotional breakdown, and the second after slitting her wrists. a few days go by, her being released and saying she felt better. a months pass by then this. she explained that her recent therapies and abuse hotlines told her the reason of her dissorder was me. she told me she wanted me to leave, but stay close so i could be nearby for our daughter. living in north carolina, i had no resources, no family, and no friends. i made the toughest decision of my life and moved back to florida where my family was. of course she wouldn't let me take our daughter, but i am uncomfortable about leaving her. my family is pushing me to file for sole custody, but i do not want to take her away from her mother. i'm torn between decisions. i know what i have to do for my daughter, but my feelings for her mother are still there in my heart. where do i start? what should i do?