Lately I cannot get into having sex with my girlfriend. I can't get an erection and don't feel attracted to her. I use to be able too easily and always found her attractive. I'm starting to notice my interest in not just my girlfriend but all women is vanishing. They do nothing for me sexually now. I don't even look at women the way I use too. Instead I'm thinking about being with men and getting erections just thinking about it. I now find guys attractive and even have fantasies. If I'm gay I'm gay and that's fine but this was so sudden. Has anyone ever heard of or gone through such a sudden change in there sexuality?