7. When a woman approached me and we hit it off
“Even when we are completely happy with our girlfriends, it’s in our genes to flirt with other women.” Many men fall under this category of having an animalistic instinct to flirt with other women. Especially if the woman shows a particular interest in your boyfriend, it will be difficult for him to resist the temptation. Make it crystal clear that you will leave him if he cheats on you.