I didn't grow up with my grandmother– for various reasons, from my dad not liking her to her own behavior– but about two years ago my mom moved her into our home. It was rocky from the start between us and simply never got better.
My grandmother is a "product of the times" kind of woman. She doesn't follow basic politeness, she likes to yell at customer service workers, and she gets very angry every time I try to make a boundary. She once worked me until I vomited and told me "we're all suffering, suck it up" when I couldn't get out of my chair for a few hours after (chronic pain go weee). I'm trans, and I've had to talk to her multiple times about "jokingly" using my dead name to get a rise out of me. I'm autistic, diagnosed, and she has always felt that meant I'm not an adult and cannot be respected as such. I have ARFID and likes to stock the house with food I can't eat– it would be one thing if she was the only one paying for food, but she's not. She only pays a third of grocery bills, but "I won't pander to you". She only stops any of this if my mom steps in, because she actually listens to her– and my mom, while I love her, would rather eat glass than yell at someone.
I'm moving out in Jan to dorms, and I don't plan on coming back while she's living in that house- my college has programs that should let me work there during breaks. I intended to live at home while getting my degree, but living here has become unbearable due to her. To keep the peace, I've not said as much to her, though I planned on leaving a short note explaining I wanted no contact once I was moving out.
My grandmother wants to give me money (she mentioned around $50) for Christmas– I'd already feel leery about accepting a monetary gift from someone I plan to cut off anyway, just for the fact it'd be a dick move, but my grandmother is very possessive of money and she WILL leverage it against me as a guilt-tripping tactic. I told her politely that I'd rather not and she didn't need to do that, but she ignored me while talking about writing me a check soon. Now that I know she intends to do this, how can I refuse it without causing a massive blowout before I leave?
**tl;dr**: I'm going no contact with my abusive grandmother but she doesn't realize. How do I refuse a gift?