Could you just position your bed so you can't see the TV from there? Easy and free. Best would be to position the TV at the head of the bed, facing away from the bed.

I like the idea of thumbtacks holding a lightweight fabric to the ceiling.

If you like the idea of a folding screen, you could always make one if you can't find one easily. Or even just a couple of sheets of plywood and craft a base for them.

Lots of people use various Ikea bookcases as room dividers.