As it turns out, there is hope after all!
Luckily for me, I saved my last .exe file in my Downloads page, for the installment of the version of FL Studio that I had when I installed it, and I can make music again!
HAD I NOT KEPT THAT .EXE FILE, I WOULD HAVE BEEN SOOOOOO BONED.
And I thought I was boned, but evidently, the bone has not dug deep enough to finish the job!
The issue is that I can't update, which means I can't collaborate with any artists with any version that isn't 12.3, which was the whole reason I tried to update it in the first place.
I can still make music, and I WILL still make music, I just won't be able to get the new fancy schmancy stuff. But that's okay, because I wasn't ready for that anyway! ;)