AITA for asking my if mom she got my bf a christmas gift?

I’m 23F and have been with my boyfriend (23M) for 3 years. We’re both young, he’s in college, I’m just barely out. For holidays, we do gifts as a couple, usually I buy for my fam and he buys for his, but it’s from us both. Otherwise we’d go broke. His family gets me gifts every year and my dad gets him gifts. It’s always been fine.

Recently, my mom and I talked out an issue where I didn’t tell her about my dad’s third kid because she wasn’t in a good mental space to hear it and they’re no contact. She told me not to tell him any of her stuff so I thought i’d respect that both ways. She said no, just not her stuff, she wants to hear about his. Whatever, it was worked out.

Last night, we were talking about Christmas Eve. She’s going to my family’s party and wanted me to stay home with my dog because it’s his birthday and she doesn’t want him alone. I said that was fine, but me and my boyfriend had somewhere to be first, so we’d come after. I also told her she could give us our gifts then.

Then she said she didn’t get my boyfriend anything and went off about how he’s “just my boyfriend” and that it’s strange I expected her to get him something. I explained we’ve been together 3 years and reiterated that our gift system is always “from both of us,” but she kept bringing up that he only bought her flowers once and he never does stuff for her. She also compared him to her cousin’s girlfriends. I told her I don’t care if she didn’t get him anything, he wouldn’t notice, and it’s not a big deal. Me and my boyfriend pick gifts for each other’s families too, so even if he didn’t buy something, he helps me pick it, and vice versa.

Then things escalated. She said going forward she won’t talk to me, I told her good luck getting my grandparents from the airport if she won’t speak to me cause how will i get any info? She said “they’ll have to Uber because they don’t have a granddaughter anymore.”

I asked if I could pick them up without her because I didn’t want to drive in a tense car, but she said no. I told her she’d rather turn them against me than talk to me. I then said it feels like she’s only nice to me while my grandparents are away. They’ve been gone a month, and when they come back she doesn’t need me. After that, she started screaming, calling me names, saying she doesn’t want to talk to me anymore, that we won’t be speaking, and that I’m a terrible person. She said things like “YOUR MOTHER IS DEAD! YOU HAVE NO MOTHER!” and She also said my dad left his “filthy spirit” in me. I wasn’t perfectly calm; I responded aggressively at times too because it was scary.

After this, she called her sister at 12am. I didnt answer cause I have work 7am. I still haven’t messaged or anything.

So, AITA for how I handled this, and for not answering her sister..?

EDIT: Thanks everyone. It’s hard for me to be able to tell sometimes if im wrong or not because my grandparents and extended family start ganging up on me. I am seriously considering no contact but I have a dog that lives with my mom who i’m really attached to , I’m also the only child but I agree it’s probably what’s needed for my mental health, maybe low contact.