Is it wrong that I told my crush to stop talking about his girlfriend?
Why don't you like him talking about her?
He's too passive and cuddly with her.
If he wants to talk about his girlfriend, who are you to stop him? You shouldn't just tell someone to stop talking about their partner because you don't like how they act together. That's super controlling!
Should I just be quiet?
In this scenario I think it would be best to stay passive. Your crush is in love and you missed your opportunity for now. You won't be winning any points with them if you don't support and share in their joy.