+1 on just getting out and having some fun on your bike. It does sound like you burned out a bit.

Are you generally pretty goal-oriented?? And so, without a goal, you're having a hard time getting yourself psyched? If you do need a goal to get going, can you find a charity ride in the fall to shoot for? (As SFA suggests.) Something less than a century---maybe 25 to 50 miles---an event that will make you feel great about participating, because you're raising money, contributing to a good cause?

How about loading the bikes up and heading outside of the city for a day or weekend of very casual, low-key cycling? No pressure, just a chance to enjoy pedaling and watching scenery go by?

Whatever you do, don't beat up on yourself for being slow to warm up to cycling again! If you loved it enough to ride a century, you can find that spark again. I bet the moment you put foot to pedal someplace pretty or in the name of getting in shape for a fall ride, you'll find yourself smiling! It might take a bit of work to get back in shape, but you've got it in you, that's for sure. No one can ride a century who doesn't have built-in get-up-and-go and a true passion for cycling!