At least every month, most commonly after prolonged sex, I develop a large red, inflamed rash in between my buttocks. It's itchy and feels very raw. I've noticed that there are possibly large blisters that usually go away and don't break when the inflammation goes down. I've gone to my doctor to have a herpes blood test and told her about my symptoms but she doesn't' seem to listen to me and was pretty insistent that this was acne, which I don't think it is. The rash goes away on it's own in about 1-2 weeks but I've noticed there has been discoloration that stays. This has been going on for almost a year now. Any insight would be appreciated. Thanks!