Holding On Letting Go

I was watching an episode of It's Always Sunny in Philadelphia on Netflix the other night, and one of the characters said the funniest thing. He said " That's all parenting is, pretending you know what you're talking about, and jamming it down your kid's throat" Man, that show is so hilarious. I think that's what my adoptive parents thought when they adopted me. All they had to do was keep talking about God and Jesus, and eventually I would see the light so to speak. I mean, I met them while I was in a Christian group home. What was I thinking? I remember that the people who ran/worked at the group home were super strict/radical some(me) would almost call crazy/militant so I think they seemed "cool" in comparison.
I remember they made me go to church with them in the beginning. My adoptive dad, let's call him M, his side of the family is SUPER religious. Like the kind of religious where it seems like any kind of love or light, or laughter is considered a sin. Like going to his mothers house was a lesson in depression. It was suffocating, uncomfortable and just plain miserable. Even during holidays, no joy, no peace, just anger and religion.
Through the years church was used a punishment, when I would stay out too late, or do whatever to piss them off, well, one of my punishments would be church.
One of the greatest things I learned while living in Seattle was that it's okay to not be a Christian. I mean, I knew it was technically okay, but it was also shoved down my throat that while it was okay, you pretty much are a piece of shit who's going to be tortured for all eternity.
As I'm working through my anger, which comes and goes. Anger is a very brutal beast I've learned. Anyway, as I work through my anger, I'm coming to the conclusion that this is really no one's fault. They are who they are, and they feel very strongly about God and all of that. But I also am who I am, and I was raised with different beliefs. The problem is that with them, and to be honest most Christians I've met, it's their way or the highway.So, they are who they are, and I am who I am.
My anger comes from the fact that they just arrogantly assumed their way is right, and they just thought I would denounce the beliefs I have and was raised with.
It became unbearable to have any conversations with D, (adoptive mom) because the root of all of my problems according to her is the fact that I don't allow Jesus in. She is unable to see any good in me. All she can see is that Jesus is not my savior.
I'm trying to let go of the anger I feel towards them and it is so hard. I have no relationship with them, and I genuinely don't want one, but I do want to lose this anger. Because even though I have no contact with them, I'm still allowing them in my life. I don't want to hold onto anger and resentment for the rest of my life. That's one of my biggest fears. I hope writing about it becomes a release.