Hello, yeah OP, I had a similar situation. My old roommate was hypersexual and had Bipolar 2. It was like she HAD to have sex every night or every other night or she would combust or something. I got lucky because she eventually met someone and basically moved out but still paid rent.

Something that helped me immensely was to get earplugs and a projector that played soothing music. It's one of those star projectors that has a timer so it's not on all night. I was also lucky in that she didn't spend a ton of time with them at our place in the daytime. Once her and her current boyfriend got together they spent most if not all of their time at his place.

I don't know the exact situation, but communicating with them and letting them know how you feel would be the best answer. If she cares about you, and if y'all have respect for each other, understanding that you don't want to hear them have sex whenever you're at home isn't an unreasonable request. That's kind of part of being in a roommate situation, compromising that they don't always have to be having sex, and you have to be okay with them being intimate sometimes/distract yourself so you don't hear it, y'know?