A Secret I've Kept for Years

I'm in my early 40s, a married professor at a small college. We've been together over two decades now, and our marriage is stable and happy. Yet, there's something that I've never told anyone about, not even my spouse. It happened during a particularly tough semester when the stress was overwhelming and my workload unbearable. One night, after grading essays until late, I found myself in a local bar down the street from campus. A colleague of mine, let’s call him Tom, who teaches evening classes, came by for a drink. We had always been friendly but never anything more than professional colleagues. That night felt different somehow. Tom noticed my state and tried to cheer me up with conversation and stories about his students’ antics. As the alcohol loosened us both up, there was an undeniable tension between us. He made a joke that wasn’t funny at all, and we shared a laugh anyway. We talked until closing time, and as I got ready to leave, he walked me back to my car. It was then when things crossed a line. We ended up spending the night together in my office building, taking advantage of empty classrooms and late hours. The affair felt clandestine and illicit; it wasn't anything like the usual married life I had at home. Yet, the novelty and taboo nature excited us both. It happened only that one time, but we’ve never brought it up again. Even now, thinking about how close to disaster things could have gotten makes me feel ashamed. My marriage has always been built on trust and honesty, yet here I am with a secret I’m terrified of even whispering aloud. The experience was fleeting but felt like a betrayal all the same.