I got pretty antsy around my one year anniversary. I think that is pretty common, but it is definitely not a reason to use. Stay extra close to your program--and finding some service work is good too. In the meantime, try to remember to be grateful for all you have accomplished in the past year, and for all that you have. I know an attitude of gratitude almost always helps me.
Hang in there--one day at a time!
Hugs--