Always have copies and copies of the copies if you're working on something so important.

There is a way to recover almost all of it. Just go to your backup drive or online backup service and get the good data back. Oh, you didn't do that? You mustn't have cared very much about your "art."

It is possible that the backups were lost too...

Sorry you had to learn the hard way why you Never don't have backups of important projects. Sucks when your tech goes bad, but no physical tech lasts forever and you have to plan for that.

Maybe OP was doing it on something other than a computer? Like a game system or something. Those are harder to make backups on.

It seems like you now learned to back up everything... Everyone learns this lesson eventually when years worth of data that is important to them, like pictures, are lost because their phone or computer dies without a backup.

I of course don't know the details, but there are many ways that lost data can be recovered. I personally have had data recovered from hard drives that have been burned or run over by a car. Check out your options.