I’ve been experiencing painful sex for 5 months and no diagnosis or treatment has worked so far..

I began to experience painful sex alongside bleeding in March of this year. I went to a sexual health clinic and was told it was likely there was an infection, subsequently I was put on doxycycline. Results from the tests came back in this time but all negative so I was confused but reassured this would have cleared anything up. My partner and I tried to have sex again (he had also got tested and came back negative) but I was still experiencing pain and bleeding. After some googling I came to the conclusion I had thrush (because I also had thick discharge but no itching), I inserted a pessary and thought this would work. We had sex again and it was better - there was no bleeding, and it didn't feel so painful. Discharge from this point was more normal. By this point its July and I felt thrush had come back because I felt increased discharge and it was thick. Bought and took a tablet for it but symptoms did not disappear. When we had sex again the pain was back, not as much bleeding but still tinted (almost like the end of a period). The bleeding continued into the next day. I had a call with my doctor and swabs were taken to rule out thrush, and that came back negative. However, I was still experiencing pain (being now the main issue, the bleeding was much less than initially). Having spoken to a Dr again I was diagnosed with PID and put on metronidazole and ofloxacin (may not be correctly spelt) for 2 weeks. Post this course, my discharge looked healthier so I was feeling more optimistic, but my partner and I had sex again and the pain was still there.. at this point I'm at a loss. I feel like I'm letting us both down and I can't figure out what is wrong or how to prevent the pain. Last time we had sex I took Ibuprofen to take the edge off which helped, but that can't be a long term soloution. For context, the pain is now predominantly felt on entry and exit but occasionally during sex like a burning sensation but not deep in the pelvis like it was prior. After sex is almost worse as my vagina swells and becomes incredibly tender (that can last for anything from a few hours to a few days). If anyone else has experienced anything like this I'd love to hear your story, it's really getting to me now. I'll definitely contact my doctor again but I really have no idea what to expect or what to do. I've always had a high sex drive and had no issue with sex before so this is a huge change to my sex life and I'm struggling.