Firstly, some snakes will just stop eating during winter. It's no big deal. But, if you don't think its that kind of refusal to eat, then I would just give her what she wants. I have a ball python that was a mouser for a LONG time. She just refused rats no matter what. So, I'd buy two or three mice at a time and feed them one after another. She would also only eat live, so I had to find some way of keeping three mice while slowly feeding them off one by one. (Sentimental me had to keep the mice that were not currently being eaten out of the room of the "carnage." I didn't want them to know death was coming. I'm a bleeding heart; I know.) Anyway, I was finally able to switch her over by getting her used to f/t mice and then one day sneaking in a f/t rat. Once she'd eaten it, she was ok eating live or f/t rats. I had to be sneaky.