Actually, if you re-read what he actually wrote, you will see that he had, in the past, an attraction towards men, had one homosexual experience, and now finds himself only attracted to women.
Let me underline it for you, just so you may properly understand: He is now only attracted to women.
Now also, assuming he, or any person, is attracted to his own sex as well as the opposite sex, that will make him at least Bisexual.
Funny how guys like you have no problem picturing girls being bi, but if a man likes both, he's labeled gay.