I've told very few people, but of the ones who I did tell I dealt with a bit of this. I shouldn't say a bit because a couple of those people I've told about my issues made it a point to drill, "Mind over matter" into my head and also described my situation as, "You're making this up and turning it into reality." It became so bad that I actually started to believe them. I was just convincing myself something was wrong with me and being overly emotional (which is interesting considering that I very rarely cry or allow myself to "feel" or deal with any emotion that comes into my mind). Then after my attempt and being sent to the hospital, one of them kept saying I was being over dramatic and a selfish wimp. He didn't listen until the doctor sat him down and told him something (to this day I don't know what he said). Ever since, that one person just stays quiet about it and doesn't bring it up. If it's already brought up by someone else, he makes it a point to say something discrediting the issue.
Because of this experience, I now have this (could be) false belief that everyone believes I'm making it all up. Hell, I still catch myself repeating what they've said in my head. It's a nightmare and probably the leading cause for my panic attacks and several melt downs. It's also one of the culprits behind why I've waited so long to seek help from a professional and won't commit to seeing one regularly. It's caused a lot of harm and a lot of distress.
I think that a good way to handle this sort of thing is to remind yourself that it is real to you and that's all that should matter. You deserve validation and sometimes you're going to be the only one willing to offer it.