AITAH for not being home when my grandparents showed up to take me to my half brother's baby shower?

I (17M) have a pretty fucked up blended family. My dad and mom were both married before and lost their spouses before they met each other. My dad had two sons with his first wife. My mom had three kids, a daughter and two sons, with her first husband. I'm not sure of all the timeline stuff but they were 9 and under when my parents got married. My parents were in marriage and family counseling to help everyone blend but they didn't blend. Dad's kids are dad's kids and don't want to be mom's kids or stepkids or mom's kids' siblings and mom's kids feel the same way about being mom's kids and not dad's kids or dad's kids' siblings.

My parents had been married for 4 years when they had me. CPS had to investigate when I was a baby because when one or some of my half siblings were supposed to be babysitting they left me alone and a neighbor went out to check because I was crying really loud. I think I was 7 months old or something. I wasn't removed but my parents had to attend classes and my half siblings were punished and put into therapy again.

I don't remember having a relationship with my half siblings. I remember some of them living here and ignoring me when they lived here. And I remember the fighting they used to do with mom and dad. Dad's kids used to call me shitstain when they'd fight with him. Mom's kids used to called me a r-word mistake in fights with her. That's really all I remember. They don't talk to us anymore. My mom had some contact with her kids for a while when they first moved out but that stopped too. I don't think dad had any once they were gone. My extended family on both sides has contact. Some of my half siblings are married and some even have kids. Extended family were invited to those things but we weren't.

My parents have talked to my grandparents lately about finding ways to get me in the lives of my half siblings or at least to make sure I'm known by their families. One of mom's sons is expecting a baby with his wife and the baby shower was last weekend. My parents and maternal grandparents decided I'd join my grandparents for the baby shower so I could interact with mom's kids and their kids at the shower. I didn't want to go and I wasn't invited. But my parents and grandparents said I was going. Dad's parents said they'd bring me to the next party they were invited to and we'd work things out that way. So I should let the baby shower be the start of reintroducing me.

Instead of letting this blow up in my face, because I'm pretty sure my half siblings' anger would be mostly at me and not my grandparents, I left the house early Saturday morning and I didn't come home until late. So I wasn't home when my grandparents came to take me to the baby shower. When I got home it was a shitshow and my parents were angry and my grandparents called to the house that night and told me I had wasted a chance to reconcile with my siblings. They said everyone was there from mom's kids to her grandkids she's never met.

My parents took my stuff for a few days as a punishment and I got a lot of you shouldn't have left like that and stuff of that nature. They told me I won't do it next time and I behaved like a kid instead of like a young adult. They do not care about my side and every time I tried talking to them they told me they make the decisions, not me.

AITAH?