Secret Santa to someone you hate?

Secret Santa to someone you hate?
My boyfriend and I work at the same place. Well, I was really sick so he went to get me some food where we work. The girl working asked him why he wasnt at college because it was the big OSU michigan game. And he said he would rather be here with me to watch the game. She told him she didnt know why he was with me anyways. he could do so much better than me because i was fat and ugly. Now, she has had this big crush on him since he started working here. And she meant her as being the better. Not only this, I thought we were cool but then she started running her mouth and almost made me loose my job. then she started running her mouth to me personally and when I was defedning myself i got put on a 1 week suspension but she didnt have anything done to her. Anyways, for secret Santa i picked her name. I want a gift that doesnt seem mean, but is. Like one of those gifts that they can do absolutely nothing with. I thought about a gift card to like mcdonalds because she is probably 5 foot and almost 300 pounds...but then i figured she would like that. am i just being selfish? my boss thinks its funny i got her name even though he knows all the problems I have had with her. Please help!! p.s. i tried switching with my boyfriend- who has one of my friends. but my boss said absolutely not. so thats not an option.