Wife's Secret Night Shift Surprise

So here I am, working my usual night shift at the warehouse. It’s just me and a couple of regulars who stay late to chat, one of them being Mike, a guy I’ve known for years now. We’re all about as close as you can get without actually being friends. But that’s fine by both of us; we know our limits. Tonight was different though. As the clock ticked past midnight, something shifted between Mike and me. He leaned in close to my desk and whispered, “You ever thought about switching things up a bit?” My heart raced as I realized what he meant. It wasn’t just casual curiosity anymore; it was an invitation, plain and simple. I’ve been married for ten years now. We still love each other, but let’s face it: life moves on sometimes. And there are nights when the loneliness hits hard enough to make you reconsider everything. Tonight, Mike was offering an escape, a temporary release from the routine. We didn’t do anything wild, no handcuffs or blindfolds involved. Just a kiss and some whispered words that danced around boundaries we both knew were blurry at best. It felt... familiar? Not quite right, but not wrong either. So here’s my question: Am I being an asshole for even considering this with Mike? Do you think it's fair to toy with the idea of stepping outside our marital vows for a one-time fling at work, knowing full well it means nothing beyond that moment in time? I’m not asking for advice on how to proceed; I already know what I’d like to do. But am I being selfish or naive? What would you have done differently if you were me?