The origins of my bisexual leanings

I had a "homosexual experience" when I was about 12 years old. A male friend of mine, Clark, told me how good it would feel to stick my penis in his butt. He said his brother had told him about it. I knew virtually nothing about sex at the time. I don't even remember if I was masturbating when I was that age. Clark and I were at my house alone. We went in the bathroom and both took off our clothes. I got hard somehow. I don't remember if he touched me or I touched myself or what. I know he didn't suck me. He got into the tub and bent over, and I got behind him. I think we used Vaseline for lube and I stuck it in. He told me to push it in and pull it almost all the way out again. Within just a few strokes, a mere matter of seconds, we heard the front door open as my mom came in the house. We scrambled and he grabbed up his clothes in his arms, ran out of the bathroom and into my bedroom, and closed the bedroom door. It would have been impossible for my mom to have missed seeing him. The short hallway that he crossed was directly in the line of sight of someone just walking in the front door. I closed the door to the bathroom and, when she asked what was going on, I told her I was pooping. She'd certainly seen him run by naked, and it was obvious that we'd been up to something sexual. She told my dad, and he gave me a talking-to later about experimenting sexually and the difference between "right" and "wrong" when it came to sexual things. My parents were Southern Baptists and they thought homosexuality was definitely "wrong". Clark and I never did anything sexual together again.

Maybe a year after the incident with Clark, I was sleeping over at the home of another friend, Bill. I recall that Bill and I both took off our pajama bottoms and we lay next to each other with our penises touching. I think we were both hard or at least semi-hard. We rubbed them together by sort of humping against each other. I think I got on top of him once and humped against him for a short while. Nothing more happened and we never spoke of it at all.

I didn't think of myself as gay at all after those two incidents. I wasn't sexually attracted to other boys, nor was I attracted to men later. I married a woman, had k**s, etc.

Then, probably in my late 40s, I started watching bisexual porn once in a while. Not gay porn, but bisex porn, MMF. It got me hard and became a go-to from time to time. Now, I watch bisex porn occasionally and fantasize about being one of the actors--sucking, being sucked, and both giving and receiving anal. I'm not sure I could ever act on it IRL due to fears of indiscretion and disease. I wouldn't want to do anything to jeopardize my relationship with my girlfriend. But it's still kind of on my "bucket list".