Lone wolf pretty well describes him. Lack of love in his life. No wife or kids. A girlfriend of sorts. One brother who hadn't spoken to him in 10 years. Other brother lived far away with occasional tweets. Doesn't appear to have any close friends. Some neighbors had negative things to say about him.
Relationship with his mom might prove interesting. Was he considered the "loser" in the family. He helped her with apartments she owned in Florida. No father around.
I guess bragging about his winnings was a big deal for him. His claim to fame to make him feel like a big shot with his family. And if he no longer had that?
He obviously put no value on human life as he didn't see the value in his. Sociopath. A very sick one.