I broke her heart to save mine
When I was 17 I was with a girl I absolutely loved. Soon she became pregnant and it put everything into perspective. We lost the baby and stayed together for 2 years. She was 2 years younger then I was and she had decided to move 140 miles away to go to college. I stayed close by after high school to stay with her. She was my sun, my moon and my stars.
A few weeks after she had graduated I abruptly broke up with her. I know that it hurt her more then it hurt me, but I had to. The thought of getting a late night phone call from her telling me that she made a "drunken mistake" while in college crushed me. I wanted her to have no regrets and to be free. I quickly slept with several girls to be numb and move on with my life.
That was over 12 years ago and I still think of her all the time. We both have moved on with our lives but there will always be the "what if" factor.