can you ever fully recover from insomnia?

I had insomnia for years… was barely getting any sleep, not I have got out all the things that were keeping me from sleeping and am now sleeping a ful 8 hrs a night… I feel much better however still am feeling sluggish still… ive gottin 8 hrs a night for a week. im still tired though and a little forgetful. how long to recover? I mean im probably years and years behind on sleep. DO I NEED TO CATCH UP FOR YEARS?? or after just a cpl weeks will my body forget about being so behind and just be normal after like a month of getting 8 hrs a night? help thanks