Maybe acquire an old single speed 'casual' bicycle (aka a 'Beach Cruiser' here in California) and start by riding that for a few miles/kilometers on a regular basis? You don't have to 'push' yourself, just hop on with casual clothing and ride somewhere - a store, post office, down to the beach, anywhere nearby.
Usually when I need to get motivated I just need to force myself out the front door and start pedaling, and within a short period of time I'll feel like keeping the pedals turning for the next 1.5-2 hours.