We're exclusive but he flirts other girls?

Anonymous
I've just become exclusive with the guy I've been talking to for months. He invites me over to smoke with him or nights out quite a few nights a week now. But one of his friends just told me that he was flirting with his girlfriend's friend who he met the other night and "thought she was pretty". Apparently he also went into a room with another girl at their house party which I didn't go to. Is he 'cheating' even though we're not in a relationship?
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+1 y
I can't help but feel like I'm not good enough and that's why he's flirting with other women so early on?
We're exclusive but he flirts other girls?
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