What do I do about my best friend's jealousy?
Get another go-to person ASAP!
Seriously. If you don't, I am afraid that you are going to get your feelings really hurt. You don't have to just throw him under the bus (as in announce that you are getting a better support person), but you can quietly look around and find some place else to take your concerns to. May people have found angels right here on this board, as a matter of fact.
If he is already asking you if there isn't something else you can talk about, how much support is he going to be when you actually HAVE to talk about it?
You deserve better than this. Promise.
Edited to add:
I just read the part where you mentioned that it is hard to make friends because people think you are mean. How funny!! I have problems with that, too, only not as much as I used to. For me, that came from being a little too sensitive and afraid of rejection. It's a lot better now as I have more confidence, but I still have to be careful.
It doesn't help that I (or so I've been told) have a naturally cranky-looking face. LOL