Girl Getting Too Friendly with Boyfriend?

Hey guys, I have a question.

Been dating my guy for four years. I am kind of a jealous person... I feel flashes of jealousy with pretty much every girl my guy interacts with. Most of the time, however, I realize very quickly I'm wrong and being unreasonable, cause I see him and the girl interacting in a normal way.

I have no problem with my boyfriend having female friends. However, there's one girl who has really been sending up red flags for me. I don't know her at all (he met her about 8 months ago, when they were both doing study abroad, which just ended; she's from New Zealand.)

Anyway, she comments/likes absolutely EVERY single one of his statuses, talks about how excited she is to see him on his wall, and they went sky diving together.

I am extremely jealous of her, and I feel like their friendship is crossing a line. My boyfriend thinks I'm insecure, because he says he's not attracted to her at all, and he gets EXTREMELY angry whenevr I show any jealousy about her.

So when you see a female friend crossing a line, but your boyfriend doesn't, and thinks she's just acting that way cause she's his friend... what do you do?

Updates
+1 y
Also, he says it's no big deal even if she is into him, cause she's on the other side of the planet from him now anyway.
Girl Getting Too Friendly with Boyfriend?
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