Am I wrong for refusing to greet non-mahram female relatives?

Assalamu alaikum - I’m looking for honest advice because this really upset me and put a damper on my day. I went to my parents’ house to visit and didn’t know anyone else would be there. When I came in, I found my aunt, female cousins, a cousin’s wife, her sisters, and other women from my parents’ side. They all greeted me when I arrived. My mum told me to go into the kitchen, shake their hands, and talk to them. I told her I didn’t want to, because they’re not my mahram and I avoid physical contact and close interaction with non-mahram women. She doesn’t seem to understand the difference and just thinks of them as “family.” She started shouting, ordered me to speak with them, and got so angry she almost slapped me (I moved away). My mum is usually kind, and my dad wasn’t home, but that moment she really lost control. She was loud enough that I’m sure the relatives heard her scolding me. I couldn’t handle it, so I left through the garden entrance, sat in my car, and cooled off. The whole thing ruined my mood. For me, I don’t shake hands with non-mahram women and I try to keep my distance. When I was younger I interacted more out of ignorance, but now I follow my understanding of what’s appropriate in Islam. Even if parents view some women as “close family,” they’re still not mahram to me. I don’t get why I’m being pressured to do something that conflicts with my boundaries. My mum says I’m being rude, but I’m just trying to follow my faith and personal limits. So am I in the wrong here, from an Islamic or general perspective? Or is my mum overreacting and not respecting my boundaries? How can I handle these situations better in a way that keeps family ties without causing major conflict? JazakAllahu khair for any advice.