it's a nasty situation, she's just acting 'on the edge' in my opinion, but she (and josh as well) has to respect your feelings, that you feel very uncomfortable with them being so often together in 'wrong' situations, that's what's most important in a relation, respect for eachothers feelings and talk about it, I think the way josh acted, getting mad at you, was getting you even more paranoid, the way they react when you explain it to them, says a lot
reading all the replies and your story, I think you shouldn't look at her for this situation, but at josh, I've witnessed such a situation where they all hang out together, don't do anything, but after a while she breaks up with my best friend because she's in love with the other guy, allthough I wasn't involved in the situation, I was on the edge of giving that guy a one-way ticket to the hospital. I know you said that josh didn't had any feelings for her, but you should reconsider this, because it's been a while and they hang out pretty often
to me it seems that you don't got enough reason to believe in innocence or the opposite, so I suggest you just keep it cool, and talk with them both about it, I understand it's very difficult to do it when they're together and I also wouldn't suggest it, also try to take her out more often and do more things together or ask her why she won't ask you sometimes
I got a relation for about 21months now, and when either of us feel bad about the other being around people that makes us feel uncomfortable we tell eachother and talk about, works perfect and we trust eachother completely
sorry about this being so long, I just can't seem to shut up :p
Ps one more thing, I only pointed out the bad things so I'll correct that now
look at what you got now, you're together for 5 months, she is still your girl, she shares things with you that no one else gets while you don't even go to the same school, I don't know how often you see eachother but I think that you're doing pretty good for your age :D
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