AITA for "ruining" a holiday dinner by crying after my sister called my bald patches disgusting?

AITA for "ruining" a holiday dinner by crying after my sister called my bald patches disgusting?

I eighteen F had a tumor a couple of months ago. I had surgery and have been healthy since then, but hormonally I've been all over the place and medications have been giving me reactions I've never had before. One of them is that a new medication my oncologist put me on has been causing my hair to thin and fall out. It's something I'm deeply insecure about and honestly just super embarrassing. I'm worried I won't be pretty again. I have a couple of headbands and scarves I use to cover up the worse parts of it.

My sister sixteen F likes to tease me about it. She constantly tells me that my bald patches look "disgusting" and that the head coverings just make it "more obvious." She says it's gross and that I should stop trying to hide it because it "still looks bad anyway." She even said that looking at me makes her want to vomit.

Because of her comments, I didn't want to go to one of our family's holiday dinners. I couldn't stand the idea of relatives seeing me for the first time in several months looking so awful, and judging me or talking about me later. I know it's just hair, but it makes me feel awful.

I've spoken to some of my friends and my therapist about how I was feeling, though, and they all said that they think I ought to go out and live my life no matter how I look, and my aunt makes really nice pie so I ended up going, just with my headband.

Almost immediately after I arrived, my sister started making comments under her breath. She asked if I was "really wearing that thing again," said my bald patches looked "so bad lately," and told me I was "brave" for showing up looking like that. I tried to ignore it.

During dinner, she didn't stop. She leaned over and whispered that my headband looked stupid. When someone across the table glanced at me, she smirked and quietly said, "See? Everyone's staring." At one point she muttered that my bald patches were "disgusting" and that I was ruining the holiday vibe.

I promise I tried to hold it together, but at some point I started tearing up, and then I was full-on crying at the table. My parents asked what was wrong, and before I could stop myself, I just broke down and said my sister constantly mocks my hair loss, calls my bald patches disgusting, and won't stop even when I beg her to. I said that's why I almost didn't come at all.

The table went completely silent. A couple of relatives asked my sister why she would say things like that, and one of them told her it was cruel. A lot of people were very distant from her for the rest of the night.

My parents say I that I need to be the mature one and let it go. They say she didn't mean it the way I took it and that crying at the table only made things worse. They also say that it's just hair and I should know from all the medical treatments that it's not the worst that could happen to me, and now I'm causing our family members to be mean to her for just being a child.

AITA? I just felt so humiliated and couldn't take it anymore. AITAH for not wanting to provide a whole Christmas for my sister's kids?

I thirty-seven F have two children, five M and seven F. Their Christmas gifts are already bought and paid for, and their Christmas is settled. My sister, thirty-five F, have two kids of her own, two M and four M. My sister's husband died in September, and the grief has absolutely destroyed her. It has prevented her from celebrating holidays with her kids. I have been very supportive and have been there for her and her children. I took her kids out trick-or-treating with mine when she was going through a very big wave of grief and felt unable to. I have also taken her kids to my house for the weekend when she needed a break. I have never invalidated her grief.

We know Christmas this year is going to be extremely tough for her and her kids. My whole family and I made sure her kids had plenty of gifts because my sister felt like she wasn't able to go Christmas shopping without breaking down. I'm in a bit of a tough spot as I recently got into a minor car accident nobody was hurt and need to pay to fix damages, while my husband and I both work paycheck to paycheck.

Recently my sister called me and told me she didn't feel like her kids had enough gifts. I told her that I'm sorry if she doesn't think it's enough, that I tried, and I don't really have much spending money since all of the money I'm making is going towards fixing our car and groceries or other necessities. I let her know that she can always order some more gifts online and have them come after Christmas if it's too hard to go shopping in person, but she was adamant she wanted them to open everything on Christmas. I got a bit upset at this, because I really tried everything with the situation I'm in. My parents stepped in to get her and the kids gifts as well. I understand grief can cause people to be irrational, but I can't help but feel annoyed at the way she's treating my help. So, AITAH?