Just to add to this, because this reply is great, but 4. also don't feel ashamed to fantasize or watch gay porn either. Hell, sometimes I watch stuff I'm not even into it just kinda fun to look at. It should be fun. Nobody has to know what you do in your spare time. You mention shame, but shame is just a feeling of inadequacy that stems from what others may think of you. If you don't think of it as a big deal (and it isn't) it's nothing to be ashamed of. It's easier said than done, but there's no reason to feel gross. You may not like it, but it isn't gross.

I would not recommend conversion therapy but maybe cognitive behavioral therapy to help you with how you think about yourself, and better train your brain to not feel shame and to come to terms with how you feel. Or to develop better thinking habits, from a more positive perspective.