You stuck around as long as you could. We all have limits. I struggle with mixed feelings of guilt (for distancing myself from an abusive person) and relief (that I no longer have to be close to that person). But he cannot use his depression as an excuse to abuse another human being. I really hope he heals because there is obviously so much pain inside his heart. But you can now let him go because 1). You are important. 2). He has a family who will take care of him. Keep him in your thoughts and prayers and leave him in his family's hands. Helping him will only place you in an unhealthy situation. He is not ready for a relationship until he overcomes his own struggles. You sound like a sweet, compassionate person to care that much, and I hope you will find a good man and happiness in the future.