If there aren't any gyms in your area, could you take a fitness class together somewhere closer? My husband and I do karate together twice a week (we've both been doing it for over a decade, it's how we met :) ). It's an activity that we both love, so it doesn't seem like work.
Depending on where you live, I would consider joining the gym despite the commute. We go to a gym with tennis courts, racketball, basketball courts, etc. We like to go play games together (usually squash or basketball). It's way more fun than going to a gym to do cardio machines/ lift weights, so we're much more likely to go. I would recommend this ESPECIALLY if you're like me and live in a place with harsh winters- running outside is pretty much out-of-the-question 6 months of the year.