Asking about sexual history is a part of a history taking by physicians and I highly doubt that they meant to be rude or abuse you especially with so many people around.
Since i don't know what was asked, it's hard to comment, however, i think you need to find out who to talk to Hospital Administrator, whose job it is to deal with complaints against medical staff - at the hospital where this occurred absolutely. Personally, I think you have been abused for sure. There was absolutely NO NEED to drug you and then ask you ANY questions, let alone those of a sexual nature. I'm really sorry that you're not finding any relief for how you're feeling with the therapist that you've seen. I think you should sit down and write up a document explaining your complaint, and ;p see if there is anywhere on the hospital's website you can post it, For instance, here there is a site where doctor's are rated. Bring the document with you and ask to talk to the Hospital Administrator. Tell them that you are experiencing symptoms of PTSD; and you have not found a therapist to help you with that, and tell them that you want them to refer you to a therapist. I'm really, really sorry that you are so upset by this. I would be too, no doubt about it.
If you can talk to a lawyer, and ask about suing them for drugging you and then asking sexually charged questions, i might also check into that, and have your lawyer send the hospital's lawyer a letter. Settlements have been made for less just to have this go away, or not to have you post the incident on the internet. THERE IS NO WAY THAT DRUGGING A PERSON AND THEN ASKING THEM ANY QUESTIONS ABOUT A PERSON'S SEX LIFE, ESPECIALLY IN FRONT OF OTHER PEOPLE.
You are RIGHT to be upset. I'm sorry. I'm sending you a hug as we speak. Feel better. I'm here if you want to talk privately. :).
My guess is, you misremember what happened due to your being heavily drugged with fentanyl. That's more believable than a whole room of medical professionals listening while you are asked very very inappropriate sexual questions. Maybe you could go on from there, rather than pursuing lots of therapy?