The Long-Term Decision I Regret

So, here's a bit of context: I've been with Alex for five years. We've built our lives together, got through rough patches as well as good ones, and there’s no denying we have a strong connection. But you know how it is; sometimes life throws you off balance in ways you don't expect. A few months back, my best friend from college was visiting the city for work. She's someone I've always shared everything with, even before Alex came into the picture. One night, after we were out late celebrating her career success, there was a moment of drunken vulnerability between us. It started innocently enough, catching up on old times and laughing like only friends do, but as the night wore on, the air seemed to change. We found ourselves alone in my apartment with that unspoken tension hanging over us. And it happened, we were both drinking heavily, there was no excuse for what came next. In retrospect, I realize we didn’t really mean anything at all; it was more about seizing a fleeting sense of freedom and release from the monotony of our lives together. But still... knowing that she's back home now and everything has returned to normal doesn't make me feel any better. It's like this little seed of doubt planted itself deep within me, gnawing at my resolve with every passing day. I keep asking myself if there’s something missing in what Alex and I share or if it was just a momentary lapse during an unusually stressful period. But honestly, even after everything calms down again, that question stays open-ended.