Because mc isn't out. His friend figuring out he's gay and dating a guy is fine, but coming up to them when they aren't ready and saying 'so you're dating *guy*' would just terrify him when he's not ready. The ML is right, he shouldn't talk to him about it, just support him without mentioning it, until mc mentions it himself. Mc is absolutely the type of person who will cut off all contact and run away if his friend said anything because even though he knows and trusts his friend, because he expects that if anyone finds out, they'll turn against him and abandon him for being gay.
Its the same reason a lot of people never come out of the closet. It's hard to trust people even if you love them when it comes to a core part of yourself like that.
That’s a fair view, I didn’t take that into consideration.
I don't understand why the MC is being isolated from the knowledge that the people who love him will support him. Like, why keep that info from him? I keep hoping that it turns into some sweet mass reveal and not something toxic.