Is It Cheating?

question for a friend... Is it cheating/suspicious if your otp w your bf and friend, and he and your friend are talking about things he likes, but everytime you want to chime in or just talk to him, he acts extremely rude towards you then continues to talk to your friend, and then when you talk to him about it, he says that your being weird and overdramatic? i just need to know b4 giving her advice on what to do next.