For years my father has had a relationship with my cousin (my mothers niece) and it has been draining my emotional life for the entire 10 years. My cousin has been anything but kind, the exact opposite and since we are very close in age we both have acted in our younger years very immatruly towards one another. I have wished forever that my father choose us, his children and remain loyal and stop his relationship with her but he hasnt. 

4 years ago they had a baby, and it was at this point that I choose to remove myself from his life completely. I love my new brother but due to the fact that I harbour unfriendly emotions towards his mother, I wanted to remove myself from a growing and innocent child. But my father being a selfish man, has made the transition into cutting ties very difficult. 

We are going on a trip to celebrate the life of my oldest brother who passed away 10 years ago, and I wanted to attend this trip with friends and my siblings (those of my mother and my father) and my dad has now been invited to the event. I have cried now for over an hour and feel drained. I do not want him to come at all.

If I ask him to not come, my other siblings will be mad, and see me as the bad guy, and get mad at me for defending myself. If he comes he will only bring me further hurt, and sadness that the man who was once a great father no longer exsists. 

I want to do the right thing for everyone, but I can't help but feel like whats best for me is maybe not best for everyone. It hurts alot to be put in this position not wanting to hurt anyone else, but knowing in the end I will be hurt. 

Any words of advice would be greatly appreciated.