My friend is with a girl I used to be with.

For backstory, I (23m) met this girl (20f) a couple months ago at work and we hit it off. It was great at first however I found out I was a rebound to get over her ex so once she got bored she left me for another guy. It hurt for a while since this was the first girl in a long time I really liked and I felt like an idiot and just used.

Throughout this whole situation, I was venting to my close friend (20m) telling him how I felt about the whole thing. He would give me advice and listen to me and it felt nice knowing he cared. He said if she ever tried to get with him he’d brush her off because he values our friendship.

Well, I found out recently through my best friend that during the entire time he was giving me advice and telling me she’s no good, they’ve been seeing each other. So, the whole time I was venting how I felt he was actually talking to her. He texted my best friend saying that I seemed distant and it’s probably because of him hooking up with her. My best friend said that’s probably it and he just replied with “oh well”.

I know she’s not my girlfriend but I can’t help but feel hurt about all this, mainly since I was lied to.