Thank you Slkxx. I want to talk to someone I trust but I am so afraid if I tell my best friend she will tell her husband, which is understandable. I completely trust her to not judge me but if her husband finds out his best friend is an ex of mine and I just don't want this to get around our group of friends. I have been lucky in the fact that the guy who gave it to me has been there for me but it isn't the same. Confiding in him is just making his own struggle more difficult as he feels terrible for what happened but he did not have any bad intentions. As it turns out finding out led to answering a lot of questions he has had about other health issues he had. So in a weird way this happening may actually help him in the long run with giving him an avenue for treatment. I don't want to pile onto his issues even though he has caused mine because at the end of the day he is a good guy who had no idea what was happening. I'm so glad you were able to talk to your friend and I truly hope the suicidal thoughts become a thing of your past. I am here if you need another ear.
Various reasons are possible, including: genetics, immune system, triggers (e.g. stress), lack of nutrition/exercise, bad luck, etc.
No one person has the exact same experience. Have you tried antivirals?