Bro, you are not a victim you are a survivor. You are capable, motivated and resourceful. The perfect family is ideal but often it's not so. Most families are dysfunctional in their unique way. A fuck up son, an arsehole parent, a useless daughter, a cheating parent, etc etc. Once we know the root of the problem, we can take steps to deal with it. I noticed you did not mention your mother, or other siblings. If you have them and love them, they will be affected if you choose to abundant the family. So the best option is to seek financial assistance with the government or a religious organisation if you are a member of one.
Stay on and seek financial help, or get away from your mad brother and useless father, will depend on how the ones you love will be affected.