"always feels like they're just tolerating me and i never feel liked"
I feel this way alot even with my boyfriend- I feel like he is just "putting up with the crazy lady" but ya know if they really did not like you- they would not stick around- would you if you did not like them?

"if i go quiet i'm never missed."
Same here- I go years with out seeing old buds- and then I get messages like OMG i miss you and when/if i see them (few times a few years ago) they are so happy to see me.. I would not sell yourself short is what I am trying to say... I know the feeling and yes I have gone missing then reappear some people think whatever, other people wish I would not do it.

"i never feel understood"
Know this feeling oh so well- however in the end some how crazy things come together and a few do understand you-- or atleast the case with me. I can sware that my boyfriend does not understand at all (i.e. last week my exploding thing i get) and he actually does- he discribed it a bit of a different way but over all it is the same- he feels gravity is pulling everything to him, I feel like everything is flying at me; but we both feel like "exploding" at the time....
Perhaps it is just miscommnication with things-

Also how long are you spending with a "group"... it takes a bit to know people- some people are shy and are not as expressive as others (I am this way so it took a while like 4 or 5 years for me to accept that I had some friends).....

I hope that helps a little- but I know some one on here will be able to give you more clarity than I :-) I hope it comes soon