Next time you think of caving in, instead of running and jumping on AIM, run jump on a dildo.
Pain is a positive reenforcement. After jumping on that dildo a few times, you come to resent her for making you do that to yourself.
Or better yet. When you think of her. Write down your thoughts on paper. Wait 3 days and read it again. If you still feel that way, burn the paper and believe in your little heart that the smoke will carry your words to her. After a month, you will be so tired of setting off your fire alarm at 2am that you will find other distractions.