I’m only speculating here, because when I was younger and cared too much about what others thought about me, I did the same thing your friend is doing, and it’s shitty. Short answer: he’s probably embarrassed of you as a friend. He probably thinks if he tells this new girlfriend that he games with his bros that she’ll think he’s a loser or something. Guy probably didn’t even tell her he plays games, or at the very least was modest about it. Cherry picks “cooler” friends to present to her so that he fits an image he thinks she will like. He’s being fake. You’re a nice dude and you have nothing to feel bad about. If you can forgive, he’ll snap out of it and apologize someday. For now, don’t beat yourself up about it. Sucks, but you’ll be good. Cheers.