very good i feel like a shadow when im in my friendship group

same here .people thing an lying all the time

You're not being selfish, its not your fault if your parents are falling out. They're adults and need to accept some responsibility for their own actions. Yours is not the only family where arguments get out of hand, it happens more often than you may think. I get the impression that you havn't opened up to anyone about this before, perhaps other people have similar issues but they too keep quiet about them. You're not alone in having flawed parents.

I don't know all the answers, but laying all the blame on yourself alone is not one of them.