Spinal Stenosis

I have serious issues with sinal stenosis. I have had two surgeries for this condition already. First one was amazingly successful. The second one, not so much. However, I was told it could be iffy. I have two questions I could use some help with. Since I was told next surgery would be a lumbar fusion, I am trying hard to put it off. How long is a person able to go with the really bad nerve pain without damaging the nerve involved forever? Have any of you had spinal fusion (lumbar) and had it be truly successful? How long did your recovery take? Any help would be truly appreciated. With the situation I am in, the longer I can put it off the better.