See under normal circumstances I would say that this is a total assholeish thing to do but when I was 20 I had only had one boyfriend in my whole life (sounds a bit like your second one

) then I met my current boyfriend and he almost sounds similar to your current one. He is always saying how hot random girls are in the street and he is very brutally honest but as you say i just say stuff back. He's done a good thing for me, he's made me less untight about things. Try saying you'd do one of his friends see how he reacts it's usually all just laughs where I am

This is the way I feel about it if I look at a girl in the street and I think shes attractive what's to stop him from saying it as he's a man and controlled by his penis lol :P