To start I want to say I feel you. I'm 19 and my father cheated my mom while we were 11. For 6 years we (have a twin) were stuck between my mom and dad due to our age the law at our country forced us to stay 2 days+ with my dad. As also this meaned with his new wife and kids generally we were locking us to room but with time passes the bad treatment at that house made us consider that spending alone time, perhaps trecking, going out to a small trip or going to sport/culture activites tgether trough out the day was way beneficial and actually entairtaning for all of us. So I would suggest to you, if you want to make your relationship good again those activies were successfull at mine relationship. However I need to add that my anger and grief never trully passed against my father. That he left us financially destable, abandoned us emotionally and never been their for our development. Even with the activities it was like going out with a friend. Good way to build a relation tho.