If you used the CD/Desktop version of TurboTax, then the only place your tax file exists is on your hard drive unless you took physical action to make a backup copy of it. Nobody but you will have it.
If the hard drive spins, you may be able to attach it to another computer as a 2nd hard drive and copy the .tax2018 file from there. It would be in the users\[loginname]\documents\turbotax directory of that drive.
