I was that guy too!!! Open says "the only way out is through" and I agree. The 9 step process he mentioned is very helpful. I am 44 and had a similar childhood. I have finally managed to forgive my dad because he did the best he could with the knowledge and wisdom he had to work with. I tell my 4 kids that Adulthood is the time you spend recovering from your parents mistakes. I am not perfect either but they know I Love them Unconditionally.
Eddie
P.S. The strongest person is the most Unconditionally Loving of ALL Life!!!Take the Shaolin for example they would suppress their opponents by making them pass out without hurting them. The purpose of not taking their life was to give them a chance to grow and become better people. True Warriors!!!