My girlfriend and i have been dating each for a little over a year. A month into our relationship she cheated on me with my friend. Because of that night, i have had problems being sexual with her. When we have sex i see them having sex. I can't get these pictures out of my head and its bothering our sex life. Everything we do in bed reminds me of what they did in bed and its really causing a problem with our relationship. Will this go on forever? Should we even be together? Am I the one to blame for our sexual problems even though she cheated on me?