How do I break up with this girl?

You want out cause you never reckoned shed fall in love with you despite all the attention you gave her, youll be lucky to get away from this without a smashed face from the husband.

You should be careful the next time as its people feelings and not just sex you get in the mix.

The only way you can is to avoid all contact, she wont do anything too stupid but to carry on casual is the worst thing you can do as it will never end, if you can leave the area then do so or live looking behind your shoulder for a while until she forgets about you. Best of luck

Oh boy. She's screwed up if she cuts herself when you try to leave. Reminds me of Glenn Close in Fatal Attraction. "Just one more time" won't be just one more time. You do know you should have never put yourself in the position, I'm sure. Tell her it's over, she has a husband and you are sorry you ever got involved with her. Ignore her calls, texting, etc. And stay away from her husband.

definately get away from her its not worth it she obviously wants more than just sex thats just an excuse to see you! she will end up accidently telling her man in an argument and then there will be no end to it you are young and dont need to be tied up into this change your number if you have to if you want casual sex just go to a nightclub .remember her man willgo off and your life will be hell if u pursue this .goodluck

first of all kick yourself in the balls for being "the other man"

second do it again for toying with her feelings

and 3rd just leave it ignore her cut her out of your life completely and pray her husband doesn't catch you, once she realised what a jerk your are (you no it's true) she will forget you