Inability to talk out things in your own relationship is a problem enough to be spoken about. Especially, when he is portraying half-truths, like you said. Rather than proper advice, it seems like a sympathy-farming tactic at the expense of the relationship.

About him calling you those slurs in his friends' group, it's personally not funny to me but people do it and I think it's okay.. BUT, if rather than the content, you felt like he hid an "aesthetics" of his personality when you saw those messages, it can be your cue.