My friend or my friend ex?

Ok~ So I have this friend and me and him is on good terms , so we're lik reaaaaaaaaalllly good terms. Were the best friends plus x666666 best~~ He's gay. Ok so just a min ago we was play RoBlOx and his bf came on, he then whispr me to leave the server, but I didn't want to. I then ask if anyone there was (a made up name) Jake. The dude then said no, and then im like what, and then we started talking. So then my friend is like, stop talking to him, and unfriend him. Im like why? He's like, just do it, trust me. and i told himm to trust me and hes like i can't unless you unfriend him. But believe it or not me and his ex bf are like ok friends. So then my friend got reallty mad and then he's like "Me or him"

I already have a girlfriend so me and his ex dating isn't even happening. and I hate to choose people. It's irrating and it makes me sad

I don't know what to doo ;-;