Very sorry for your incident...
... but, frankly speaking, you have now learned that a backup is a must.
With hdd the question is always “when” they’ll break and not “if”
My suggestion is to buy two (three is better) hard disks and manage with absolute rigor your backups.
The first hdd should be the “work” copy, the second should be the “master” copy and the third a second “master” copy, and keep these last two copies in a safe place.
There are many software to easily manage backups, they have the option of “incremental” copy instead of full copy, that is to say that the first time there will be done a full copy and the next only the changes/additions will be copied.
The one I use, and it is free, is FreeFileSync, it is available for Windows and macOS.
After the first copy it will cost you few minutes only to keep your copies synchronized and your files will be safe from this kind of issues.
Hope this can help