Title explains it all, but to give a quick rundown:
I've got a pack of mods for 1.16.5 ready to go, I've got their libraries, picked out the ones that turned out to be fabric, but when I start the game, it does it's usual loading shenanigans but eventually stops at a certain mod and then the memory starts to spike a bit before the game finally crashes giving me an exit code 0.

Before you say it's that certain mod causing forge to crash, it's done this with other mods, and I removed those mods but it still keeps happening. It doesn't stop at a certain one, it just seems to stop at one around that area and then it starts going haywire. Video of it with a bit more info too is here: (Not great quality, but you can see memory start spiking)
https://www.youtube.com/watch?v=hiFhNnjOJgw&ab_channel=yarknark

I don't have a crashlog or anything either, the ones I do have are from when I had to install libraries and pick out Fabric stuff.
 

HEY! I SOLVED IT! DON'T WORRY!
Because I actually found out that there WAS a mod causing problems, that mod being Chlorine, which is basically as far as I know is a sodium port to forge. So yeah, Chlorine was the issue. Might want to address it to that mod's creators.