Separated Parents

I always grew up thinking my parents will be together because they were high school. I noticed them arguing and fighting about my father stepping out of the marriage when I was young but I didn’t saw anything. After that, i thought everything will be good. In high school, they were separated and I lived with my mom. My parents have their own lives and I know that my father isn’t faithful to anything. He does not help my mother financially with my youngest sister. I used to be a daddy’s girl but I grew out of that because I saw the things he do. The problem in this family that we don’t express our issues and I barely spend time with him. Just because I’m grown( I’m 21) does not mean I wanna spend time with him. Then all of the sudden he moves in with his girlfriend and she gets pregnant now I see them on Facebook. I hate the fact that I never really got over his separated thing kind of and I get mad and irritated when I see stuff like that. I am tired of it all, I wish we can sit down and talk but I know it’s not gone work out. Both parents are in the wrong but I feel like my father the one who caused most of the problems but my mother should’ve left him alone for good and I think he tries to be with her because he think she is gullible. When my mom moved on with her life and have a friend, I notice she is better that way. It’s a long story to tell but I been meaning to go to a counselor or just have a intervention. I do not want my children to grow up and go through this or anything because of my daddy’s father wasn’t in his life.