I was in your position, sort of, a few years ago. What worked for me was planning a major trip that involved biking. The first was a bike and barge trip in Holland, and I rode a tandem with DH. I picked Holland because it was flat, and we did the tandem because I was worried that I'd be left behind. But I didn't want to embarrass us too badly, so I rode almost every day. The trip was wonderful fun 20-35 miles a day at a leisurely pace. It was a "family" trip so there were kids along, the youngest was 10. People were from several different countries.
We barely got home before we were planning the next trip, Brussels to Amsterdam, also by bike and barge. This time I rode my own by myself, no problem, but the fear of being left behind was a great motivator to get up in the morning and get out on my bike in the months before the trip. Again we had a great time.
The next year we went to France. France is not as flat as the Netherlands. (duh, nothing is as flat as the Netherlands, even Central Illinois.) And more of the people on the trip were serious bikers. Even though I had sought out every hill in town to practice on, I was bringing up the rear on every hill. Well, somebody has to do it. I think a couple of others were glad I was there to take the pressure off. France was beautiful and we had a great time again. I was glad I'd trained as much as I had and lost the 25 pounds.
This year we rode on the Michelson Trail in South Dakota with some old friends. The rail trails are nice because the hills aren't steep, but some of them are pretty long. It was beautiful. Another good trip.

Haven't decided where we'll go next year, but the year after will be across Missouri on the Katy Trail. That's a long enough trip that I will have to do some serious training to be able to ride further in a day. So far 40 miles is my record.

DH goes on the trips and likes it, but he only rides his bike to work, and an occasional ride with me. We have a crummy tandem that we ride to church or maybe to the park. He rides a recumbent stationary bike while he plays video games. I prefer to get outside.

Anyway, that's what works for me, the pressure of having a deposit down on a trip that might be humiliating if I don't get out there and ride now. Most of the time, though, as soon as I'm on the bike, I'm glad I made the effort.

Kris