This is common in a divorced family. Whatever the issue is, you have to emotionally distance yourself more from the friction between your parents. And as a side note; it isn't very healthy for a teenage boy to be "best" friends with his mother. Especially given how hedonistic you have mentioned your mother is in past postings.
When I was about 9 I told my father that I wouldn't go on a visit with him because he wouldn't stop insulting my mother. I told him that I didn't allow my mother to insult him, and that I didn't want him to insult her. I am glad I did this, but I haven't seen him again since that day, and I am almost 33. He was wrong, but in retrospect I would have handled it differently. My father literally has half a brain, so it is a different situation entirely. I know now that as the non-custodial parent he assumed that when he was away that I didn't love him as much, even if those assumptions had no basis.
You are old enough to understand that your father isn't perfect. Try to focus on his positive aspects and forgive the negative ones. Parents are human, they sin and have insecurities. Try to affirm that you love and respect him. You aren't responsible for his behavior, you can't make him change. Pray for him and show him that you love him as he is, not as you think he should be. Attempting to correct your father will only make him feel even more unrespected. You have mentioned a great deal of frustration with both your parents behaviours in the past. They won't change because you do or do not do certain things. They have to desire to change. And whether they change or not, they are still your parents and you will/should love them anyway.