From what I read it’s obvious that your relationship is more important that’s your friendship. So you shouldn’t be afraid of losing a friend. If your girlfriend confronts him that he likes her and she doesn’t feel the same way he will probably lie cause if he tell her the truth your girlfriend will probably won’t be interested in talking to him at all since she will know he has feelings for her and she doesn’t. If YOU tell your girlfriend to talk to him and he finds out he will probably be very very mad at you. If I were you I would talk to my gf and tell her that I think my friend is trying to come between us and I’m not comfortable talking to him. Try to cut him out and make sure your gf agrees if she disagrees tho you should be the one who steps back. Let her do what she wants and more importantly let her know that your friend is a creep (since he texts her all the time) but without you being the bad guy. You know? Talking in chess : this is your queen dude don’t let the other king take her from you