AITA for not wanting to fix my relationship with my father?

Since our parent's divorce, me (16M) and my siblings (19 and 12), have never had the best communication with our father. He made the decision to move 50+ miles away with his girlfriend and her child and me and my father have had a rocky relationship since.I have put a lot of effort into fitting into his family unit from the very beginning, despite not being welcome at times, and, though I have never got along well with his girlfriend, I was always respectful, kind, understanding.However, across these three years, he has unjustly accused me of stealing from him on multiple occasions (all proven eventually as false), he has informed me that he wasn't comfortable having me in his house, he has constantly badmouthed my mother's parenting in from of my kid brother (despite him sometimes getting so drunk that he falls over), he has talked to my grandmother about my private mental health issues- ones told to him in complete confidence without even informing me, as well as punishments for my behaviour (I understand that is the role that some grandparent's play, but it was never one that she did. His girlfriend decided it would be appropriate, she should not have a say in my parenting)​Throughout all of this, I have always attempted to be the bigger person. I have always forgiven, despite a distinct lack of apologies (I am extending an olive branch was the best I got sober) and have set about building up the relationship he tore down.The final straw came when my older sibling came to me in floods of tears.My father had got engaged about a week before, my sister had discovered it as he had posted it on Facebook.She was devastated, not that he was getting married, but that he didn't regard her with the respect even to pick up the phone and let her know. She spent the entire day crying. I was livid.I waited another week, hoping he would at least drop it casually into conversation, if nothing else. Nothing. Finally, I congratulated him. I pulled together all of my humility and I texted him, wished him well in his marriage and explained very calmly that he hurt us all.He informed me that me and my sibling never put effort into texting him between visits, so he never had a chance to bring it up. It was a shock to me, as he never reached out to us at all in the last three years between visits and had certainly never expressed that he wanted to talk more. From my perspective, he was the mature parent and I was thirteen years old when he left. It was not my responsibility to maintain that communication and it is not my brother's currently.It was me that sat down my twelve year old sibling to tell him that his dad was getting married- that he would have a step- mother and step-sister.I feel like this is the last straw, I no longer want a close relationship with him unless he makes about trying to build it. Should I have tried to talk with him more, am I the asshole? via /r/AmItheAsshole https://ift.tt/341A26a