It sounds like he is bisexual, not gay.
"You either .... ...., or you do not .... ...., there is no in between." - Andrew Dice Clay
You’d be amazed at how “straight” plenty of homosexuals can pass off as before they come out and live homosexual lives. Plenty of homosexual actors, especially prior to coming out, played pretty convincing straight, ladies’ men in film. That isn’t to say he didn’t have affairs with other men on the side before he came out, but still, it’s pretty surprising how some guys who are homosexual don’t pass off immediately as such.
either way it sounds like she may want to be tested for HIV.
To quote Hemingway: ”there are no bi—sexuals, there are just fairies that screw women.”