Caught in a Moment of Weakness

It was one of those rare, hot summer nights when the air felt like velvet. My neighbor, who I've known for years but never really noticed before now, invited me over with nothing more than a wink and an unspoken promise. We shared something intimate under the cover of darkness, so brief yet electric. Now every time I pass by her place, my heart skips a beat. Is it normal to feel this way about someone who isn't your spouse? Should I tell my husband?