<human>: Can you provide a brief overview of the text?

I'll try my best to be unbiased about everything here since I know a lot of this is my fault too.

My girlfriend and I have been together for just under three years now. We get along great in every regard, and I'm head over heels for her.

Recently she made a new friend (guy) from work. They started texting, and I see some of the texts he's sending her and they're pretty flirty. I told her I think so (she disagrees) and that it makes me uncomfortable. Keeps happening, and eventually we got in a big spat over it. She says she's going to stop talking to him - fine, whatever. Over the next half a year, she continues talking to him but starts hiding it and lies 6(?) times about talking to him (and before you say she's cheating I know (am pretty sure) she isn't, and please don't factor that in to your replies). Then a while later one of her other friends asks her if she and this guy all want to hang out. She tells me (stopped hiding it at least) and asks if I'm okay with it. I tell her it will make me really uncomfortable and she goes ahead with it anyways. Another big fight, stops talking again, yadda yadda yadda. Fast forward to now, where I had almost forgotten about it, and they go out for wings with a couple other people and it all comes flooding back.

I'm at the point where I am constantly thinking about this and it's making me miserable. I don't want to make her stop talking to a friend, especially since it's my jealousy that caused all of this in the first place. But I don't see any other options.

Any advice for getting through this without her losing her friend or us breaking up? I really want to stay with this girl, but I can't get over it.
<bot>: Girlfriends male friend makes me uncomfortable after several lies about communicating with him, don't know how to fix the problem without breaking up.