It’s a little odd, but without any context I don’t see how it’s a massive problem. Is it appropriate to ask a question about your personal life and relationships as if you didn’t play a role in it?

How does he feel about this? What’s their relationship? How do you feel, and what about it makes you say it’s inappropriate? What are you worried will happen? What does he say when you talk to him about it?

This is one of those interpersonal snags that you’ll have to figure out between you. You can’t get an impartial judgement from the internet to settle your conflict once and for all.

Also, hey Matt! Good to see you again.