Just try to ride regularly. My wife and I really just started (beyond the occasional ride with the kids) about a month ago. For the first couple of weeks we were getting a ride in the morning, starting at like 4 miles. Then there was the 7 mile ride that would be every third day with a day off. In other words (ince I know I hosed that description) we did 2 short rides, the 7 mile, then a day off. Rinse and repeat. That alsted a couple weeks, but the first few days were rough on the butt, and we got sore in the thighs, but we stuck with it and enjoyed the day off.
Fast forward, and the trouble now is that the "long" ride is now a short ride and we have a hard time finding a route that we can do in the morning that's any kind of workout. Last night we did 32 miles.
I have found for myself that I am better off riding some every day taking myself to the point of being just a little sore, than trying to reach further where I have to take every other day off to recover. I've been frankly amazed at how much my possible distance has increased in a short time, and how much further I can go before my butt gets sore.