While i can't magic your progress back, i recommend using repositories like git or mercurial to save intermediate versions to avoid things like this in the meantime.
I personally recommend mercurial (A.K.A. hg) with tortoisehg (a GUI), because it is a lot easier to use than git and way harder to fuck up.
If you are only using it so save your progress it is about 1-2 minutes daily of added work, but you have all your progress saved and can even go back to older immediate versions if something got messed up in between.
If you have questions or want some assistance/guidance setting that up, feel free to respond. I know that pain, buddy. (Though i only lost a few weeks worth of effort, not months)