Ouch!

That's awful.
Did you make any kind of backups? Copied the folder of your route previous to the accident?
If so, maybe you can simply copy the folder back.
If you have RW_Tools, does it see your custom routes? If so, you might be able to make a clone or copy of it there perhaps or find some way to salvage it from there?
I know from personal experience just how awful it feels to think that you lost a project that you poured several hundreds of hours work into... a few months back my old computer was "dieing", and in the process of trying to fix it, I almost lost all of my work, backups too.. I was gutted.
But in the end after much stress and jumping-through-hoops I was able to recover some of my backups files from an external drive and my projects were salvaged. Whew!
Anyways, perhaps someone else here might have some other advice they can offer.
If you didn't make any kind of backups, then you could be up-the-route-without-brakes and might just have to take it as a hard-learned experience and start on a new project.
Remember to save often and backup often. Try to make it a habit. The easiest method I use is to simply make a Package of my project, along with my associated Developer folder for that route under the Assets, via the RailWorks built-in Packager from the launcher window (using the "unprotected" Packaging option so I will still have full editing and repackaging ability from an install of a Package) after every couple of hours of progress, so if something goes terribly wrong (which it has on a few occasions), I can just reinstall my project from the most recent Package file and won't have lost too much work.
Best wishes,
--Don.