Where do we find help for caregivers who have snapped? I have a friend who attempted suicide/homicide.

My friend is in jail on attempted murder charges. There are those of us who are helping by seeking information, studies, possibly experts, or leads to other information. This is a case of years of caregiving of an abusive child with emotional problems and a parent who tried so incredibly hard to find help and the emotional, financial, physical, stress, and lack of alternatives.

Does anyone have any ideas that might help define/quantify, caregiver burnout and it's ramifications? You who have been there understand the need for compassion. Now, to find the facts to support what you know. Thank you so much for any leads you can give.