About ready to quit...

Hit the last straw with my boss...I don't work Sundays. I haven't worked a Sunday in a year and a half. I worked Christmas Eve and I'm scheduled for New Years Eve. My boss decided to be a dumbass and schedule me for New Years day. Which is both 1) a Sunday and 2) I already worked both Christmas Eve and New Years Eve. She even asked which I wanted to work and I said Eve! I called out of work today just because I don't have any motivation to go in any more. And I don't want to close with her twice in one week. My AM was very understanding on the matter. I was shaking I was so angry when I saw the schedule for next week...She called me and left a message to call her back. I don't think I'm going to. I keep thinking I "have" to do something. But the thing is, I don't care if I get fired. Yeah it won't look great on my record, but I don't think that my boss is capable of actually firing me. Because she needs me. I'm not saying that to be cocky. I'm one of the best workers there. It's after the holiday season, but she'd be in a bit of a bind without me. She has only fired 2 people in the last year. 1 was for a very good reason, but she didn't even tell the girl she was fired. She let her come in and see her name crossed off the schedule. And the other person, we all love her but she couldn't do the work any more. She really couldn't. That was probably difficult for her to do, but it had to be done. I'm doing my job and doing it well. I've just called out more in the last 4 months than I have in the last 3 years. So there's that. She also called me on her cell...Which I refuse to answer if she called on her cell. I don't know...I don't know if I can stand going in to work on Thursday and close with her. I can just tell her that I was in bed all day. Asleep. Yeah. I don't care if she doesn't believe it. I'd LOVE to see her fire me. Seriously.