I am sorry you are going through this. I have lost several friends due to this illness. I will echo what other posters have said. It is very hard for people who are not going through this to understand what it is like and how hard it is to connect.

Yes, it is true that there are some people who just do not care. However, I have found that by sharing my struggle I have found people who are also suffering from an invisible illness and we have become closer as a result. There are also those that do not understand but want to. For those people I found resources (online comics and free games) that help them understand my experience.

I know it is hard to be this vulnerable with people, especially if you do not know how they are going to react. I would suggest that you keep at it. Your circle of friends might shrink but those that remain may end up being truer.