10. “She’s beautiful.”

Your girlfriend may try to bait you into this one by asking your opinion about a friend or family member’s attractiveness. Do not fall for it. Even if you’re just being honest, all this will lead to is a discussion about whether the woman in question is prettier than her, which is no fun for any of the parties involved.

11. “This is a man’s issue.”

Heaven help you if you utter this phrase, followed its trusty companion, “You wouldn’t understand.” Even if she wouldn’t understand, she is not going to take it that way. Your girlfriend will see you saying that as an indictment of her intelligence. No one likes to be called stupid and by saying this, you’re saying she isn’t smart enough to understand what you are dealing with.