MacBook Pro El Capitan Freezes on Boot Up

Background

I put my Mac to sleep, then realized not long after that I needed to do something else on it. I opened it back up and had a black screen and it wouldn't seem to wake back up. I pressed a few keys, waited a bit, still nothing. So I did a hard shut down (perhaps a mistake...). When I turned it back on, I could get to my user and enter my password to log in, but the loading bar would get about 2/3 the way and freeze. I have tried this multiple times.

Solutions I have tried and their results

• Boot into Safe Mode: log into user, loading bar gets nearly complete, then freeze on blank grey screen
• Boot into Recovery Mode: Apple logo appears with loading bar, bar gets most of the way done, then freeze on blank grey screen
• Boot into Online Recovery Mode: Progress bar beneath spinning globe will complete, then freeze on blank grey screen
• Boot into Single-User Mode: Message below shows up, goes away, Apple logo appears, then back to user login, it will not remain in Single-User Mode

BuildUser() : error buildng a user of type 0x20010008

Boot into Verbose Mode: Message below shows up, goes away, Apple logo appears, then back to user login, will not remain in Verbose Mode

efiboot loaded from device: Acpi(PNP0A03,0)/Pci(1FI2)/SATA(0,0)/HD(Part3,Sig18FEFC5E-22A8-4067-9D14-5B048F4 542BD)

efiboot file path: \System\Library\CoreServices\boot.efi

BuildUser(): error building a user of type 0x20010008

Reset PRAM: no effect

Any help would be much appreciated. Thanks!