Family Issues Support Group
Family issues is a huge range that go from minor conflict to major misbehaviour and even abuse on the part of individual members of the family occur. Whether you feel you are in a dysfunctional family or you're dealing with a very specific issue, this is the place to talk about it and find others who might be going through the same thing.
I see no reason to keep more than minimal contact with your mother and brother. Hitting on his sister at his stage of life is a sign of major issues.
The best thing you've done is to move 2000 miles away.
I think that you did the right thing by moving far away from them and removing your kids from this dysfunction.
All of these family members are severely toxic and you had to distance yourself and your kids from this. None of this is your fault.
Do you have any relatives at all who are able to provide you some extent of emotional support? A cousin, for example? Are all of your relatives in the same area?
I've been having family issues and I have decided to see a therapist about how to deal with them because I feel overwhelmed. Like Patti said, this sounds like the stages of grief. What about a grief therapist?