What about swimming? It is easy on the joints and great all over exercise. Great suggestions Destiny regarding small 100 cal sweet treats. My usually sugar addicted self has found fruit to be key! healthy, satisfying and low calories. Another trick (you have most likely heard a million times) Just don't keep that stuff in your pantry and house. If you can see it, You will eat it.
Good luck to all of us! We can do it!