You won't find the answer for why they are so angry and at what. They don't even know why they are that way. The best guess answer I can give you is that they are angry at themselves, the world and beyond. They aren't happy people and they haven't realized yet that they are the only ones that can make themselves happy.
The best advice that we can give you is to sit still and quietly...the answers will come when you least expect them. While you are doing this, turn the focus back on to you and your sons. Enjoy the time you spend w/them.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
