MacOS – High Sierra Freezes on Login

I have a rMBP (late 2012 model) that I recently installed High Sierra on and enabled FileVault (this has apparently been known to cause some similar issues on older version of OSX, but I found no work around with High Sierra).

Currently when I try to log into my standard user on boot up, I get a progress bar that get to ~75% progress and then freezes (I have left it in this state overnight with the hopes that it was just slow – no luck).

Restarting the computer in recovery mode (cmd+R) causes a similar issue, where the progress bar gets to about 50% and then freezes (again I've let it sit here overnight with no progress), meaning I cant use the disk utility to repair the disk.

Safe mode (shift on startup) also doesn't do anything – progress bar freezes at ~75% on logging in.

Resetting the PRAM and SMC also don't appear to do anything.

Booting in single user mode (cmd+S) lets me attempt to repair the disk manually using:

/sbin/fsck -fy/

But it repeatedly returns the error:

warning: apfs_keylocker.pr_block_count is zero for encrypted fs (0x403)
** The volume /dev/rdisk1s1 could not be verified completely.
apfs_vfstop_unmount:1405: fake mount <ptr> going away

Running verbose mode (cmd+V) on startup runs until it reaches:

en3: promiscuous mode succeeded
IOConsoleUsers: time(0) 0->0, lin 0,lik 1,
IOConsoleUsers: gIOLockState 3, hs 0, bs 0, now 0, sm 0x0
Setting BTCoex Config: enable_2G:1, profile_2g:0, enable_5g:1, profile_5g:0

Where it locks up and freezes.

I have also tried reinstalling OSX from a bootable USB drive and via WiFi. In the case of the USB installer, the progress bar, once again, gets to ~75% and freezes. Using the WiFi method, I get a grey screen to appear with a pinwheel that spins for about 3 seconds before freezing and crashing.

From reading various forum posts, it seems like either my harddrive has finally died or FileVault and High Sierra aren't playing nice together. Ideally there is some work around that I've missed, but I do have backups, so I'm okay with wiping the harddrive completely, but as of now, I don't even see a way of doing that.

Any/all advice or input is appreciated and thanks in advance for any help!