Sometimes I think they're just like us;
they get something stuck in their brains, & that's the way it is forever after.

Just for the time being, can you move the bed a little further away?

I could and put the litter on the floor but I think she'll still jump down on the bed first. I'm going to try moving her to another window in the living room and hope she doesn't pee on the couch. Maybe I'll cover it with garbage bags to be sure.

This would cost you about $100, but you could purchase a large dog crate and fix it up with litter box/pan, food, and water. Put the crate somewhere where it won't bother you. Keep her inside for several hours at a time. She'll have room to move and will likely start using her litter again. I have one of these big dog crates in my kitchen, and I bring my one mean cat in at night and bed her down inside. She is separate from the indoor cats (can't harass them), warm and safe. She has come to love this crate because it belongs to her, and she knows that it is her safe, secure night-time spot. Good luck.