Hi,
I'm a male: I did have HOCD some years ago. I had such a worry that led me to research about sexual orientation, about its biological and environmental causes. I had to convince myself I was not gay by looking at other men and feel not attracted. I don't remember what made my HOCD stop: today I'm feeling totally unaffected by the thought of being gay.
Now I want to give you an advice, which I wish I could follow entirely: sacrifice.
There is a reason why the sufferer ruminates for hours, to protect his ego.
Sacrifice by overcoming your ego: what is left is the experiencing being only.
Life is not meant to be conceptualized, but to be lived.
Asking "What if I am wrong?" is also a sign of ego protection.
Not sure if that helped.