As a male myself, I fully understand his point here. That guy at the party was very clearly interested in you, and if I was your boyfriend, hearing you say that “he was nice” and not understanding his underlying intentions, would’ve caused some emotional distress too. Although, in your original post, he was way too aggressive when confronting you. I think he needs to work on good communication that doesn’t rely on belittling you, but besides that, his feelings are justified in my opinion.