As far as getting back into riding, plan it out week by week. That helps a lot. Also challanging yourself with X amount of miles per week and per month is a wonderful way to set the goals. Use the monthly mile club thread and join in. Once you get a ride or two under your belt again, the love will infest you in a good way.
I commute a lot to work.... 80% of the time. Some weeks, I decide not to commute but I soon find the love for it. Some morning I want to sleep in and drive in but once I saddle up and hit the road, those feelings disapear 110%.
As far as losing weight goes, thats another tiger to tackle. A lot of it is won in the kitchen/what goes in your mouth, no so much riding per say.