Hey, taco. I hope this works out for you. Kitty is just trying to communicate in the only way they can: with their actions. Try not to be mad.
First of all, specklebang is my hero and I want to be just like him only with a vagina when I'm a million. :lol:
Also, I think a vet visit to check for a UTI is definitely in order.
And here's some stuff I didn't see mentioned. If you're still having problems, give it a try.
It could be litter consistency. Some cats just hate the course stuff.
Have there been lots of new people over lately? If this was formerly a family cat, kitty could be nervous about the sudden change and dramatic reduction in available humans, and the introduction of unfamiliar, untrusted humans. Trying to claim the bed out of territorial insecurity. Even a very friendly cat can get nervous like that.
Weirdly, it could that you're doing TOO MUCH washing. Scooping every day and emptying/cleaning periodically is obviously essential, but you might be doing the latter too much. Scooping will make it so that you can't smell anything, but your cat still can. And some cats get a little freaked out if they can't smell themselves AT ALL. Those scent markers are what make it "theirs."
It could be attention. My relatively new kitty had a couple incidences of going outside the box when she first moved here. I found the weirdest thing that pretty much eliminated the problem: every day when I come home, the very first thing I do, before I've even taken off my shoes or hung up my keys, is pet her for a couple minutes.
My cats used to use the litterbox, but they refuse to anymore. They scratch and scream until someone lets them outside, do their business, and then lets them back in (after scratching and screaming outside). They like the outside so much that they rather crap next to the box than in it, if we're not home. Like a message.
The message is that they know they are supposed to go in their litter box, but there is something about it that is so repellant to them that they just can't bring themselves to do it.
Could be a lot of things. Litter that's too course, not cleaned enough, territorial competition... take a look at their behavior and narrow that down. Because going right next to the box shows that they KNOW they should, and that they WANT to behave, but something is getting in their way.