A random guy approached my girlfriend while she was alone at a coffee shop and struck a conversation. He chatted with her and asked for her number . She told him that she has a boyfriend but he insisted that his motives are just as a friend and he is new to this city. She doesn't see a problem with this and gave him her number. I told her that I'm a little uncomfortable about it. Her reply was "babe it's nothing. I'm allowed to make friends." What do you think is a valid response in this situation?