Secret Fantasies in the Gym Locker Room

I’ve been a personal trainer for about five years now. I met my girlfriend, Lily, when she started working at the gym as a receptionist. We clicked instantly and have been together ever since. Our relationship is solid; we support each other, share our lives, but there’s one thing that has been eating away at me lately: My secret fetish. It all began when I was training an older client named Mark. He had some unique kinks, including a fondness for roleplay and domination. We never crossed any lines, but he talked openly about his desires, which somehow resonated with something deep inside of me that I’ve been trying to suppress ever since. One day, while we were wrapping up our session in the gym locker room, Mark asked if I’d like to join him for a night out at a BDSM club. At first, I laughed it off. But then he shared some fantasies about me, how he thought I might be into more adventurous play than I let on. That was over two years ago, and since then, the idea has been stuck in my head like a thorn. I haven’t acted on any of these thoughts with Mark or anyone else. However, it’s not that simple anymore because one day, while using the locker room, another client, a new guy, walked in. We made small talk as we got dressed, and he mentioned being into role-play sessions at home. That moment triggered something inside me. I found myself asking him if he would be interested in exploring similar dynamics with a partner. To my surprise, he was receptive but quickly clarified that he had someone specific who shared his interests. We didn’t pursue the conversation further. I am not sure why this has happened, and what’s most troubling is how much I enjoyed the idea of it happening with someone other than my girlfriend. I’ve never told Lily about these secret fantasies because she’s very traditional in her approach to relationships. How can I reconcile my desire for something more intense with my commitment to our relationship? I feel like I’m betraying her every time this thought crosses my mind, and yet the pull is still there. I need to come clean soon but fear how it might impact our relationship. There’s a part of me that wonders if I should just cut off these thoughts or seek some sort of compromise with Lily where we can explore more together. But then again, this isn’t about what she wants; it’s something inside me craving freedom and intensity. I’m caught in a struggle between my head and heart.