Crashed, now in infinite automatic repair loop

[TheMaineEvent]

So my HP Envy crashed last night, for whatever reason. I waited until this morning to turn it on again. Since then I've gotten the UNMOUNTABLE_BOOT_VOLUME blue screen, and the computer restarts with "preparing automatic repair" After that, it's just a black screen. And it stays a black screen. Forever.

How screwed am I?

 

[Trouble]

Try boot the computer from the Windows 10 installation media.
On the second page after booting following the keyboard and language page you should see a link that says "Repair your PC"
Click that and use the Troubleshooting -> Advanced Troubleshooting icons to get to where you can attempt a System Restore to a point in time prior to the problem.
You might also want to try using the "Startup Settings" icon to attempt booting into Safe Mode first in case your problem is a bad driver.
At least you could then use Safe Mode boot to back up your critical data to external media, if it will boot into Safe Mode.