My graduation ceremony is being held next week. My dad had given me some money in advance to pay for the party. I lived mostly with my mom, but they were supposed to be hosting the event together. Dad and I have a rocky relationship. After my parents divorced when I was four, they split custody of me and he was able to stay a good dad. When I was ten, he met Jane. Jane had three kids, twins and a single kid. They got married when I was twelve, but I would say even before that I felt like he prioritized her kids over me a lot. He would cancel plans with me if they wanted to do something and would either do the thing with them or force me to go and say it was even better than our plans, when for me it wasn't. Think going for a hike with me versus taking them to an indoor play area, or seeing a movie with me versus Kitty Park. One more example is when I was given a ticket for a concert my dad and I both love. He was supposed to buy a ticket to come with me for some father-son time, but actually spent it on his youngest step kid who wanted their room painted. He told me at the last minute and it hurt. There were other times stuff like this happened. He didn't show up at the hospital when I broke my arm because one step kid was getting their tonsils out and wanted both him and his wife to be there. He told my mom over the phone to tell me he was proud of me for being brave and understanding even though I never said shit. When I would bring this stuff up, he'd tell me it was natural to feel jealous of sharing his attention. That was all he would say. In 2019 he told my mom he would split the cost of a trip I wanted to go on with one of my clubs because she didn't have the money all by herself. Mom had her half saved. We told my dad he needed to pay. He said bills were tight and it was the twins' birthdays and money needed to go to something for them. He told me we could do something as a family when the trip happened instead. I told him to forget it. That he was making it clear who was more important and I was going to stay with my mom where I actually met her. Mom borrowed the money to cover the other half of the trip. Dad told me he regretted making me feel less important and we were working on things and then the graduation money was given about a month ago. Then a week ago, we called and told me one of the stepkids was being bullied, how bad of a time they were having, and with that money they could help cheer them up for their birthday. I was pissed. I hung up and two days later I showed up at his doorstep, gave him the money, and told him I didn't want to see him or his new family at my graduation and that he had chosen who was more important so he better stay out of my life. His stepkids and two younger bio kids were there. I didn't stick around. He called out and told me we needed to talk it out like adults and that I had hurt the kids' feelings. His wife freaked out on me so I blocked her.

It is very clear that he's prioritizing the other children over you. You shouldn't feel bad at all for setting boundaries and for those boundaries not being met. It's definitely his responsibility to fix that.