FINALLY got the darn thing to boot. Tried countless attempts from various hints and tips, and nothing worked.
I managed to get into the System Restore area, something I had attempted but failed at, but this time, it let me.
The first and constant BSOD occurred on 07/20/17. I did a restore to 07/09/17 and I was able to login normally. Honestly, I don't know what changed since then; I don't really update or install much, but I will have to be careful from now on.