It Was Just One Night ...

Late last year, after ten years of marriage and three kids, I found myself drawn to an old friend who moved back to town. We reconnected at a holiday party... It was just one night, but oh boy did it feel good. No big deal really, we've both moved on since then, still can't believe how silly it felt afterwards though... Am I the only one who's done something like this? Is it normal or am I losing my mind here?