I am no stranger to modding Minecraft, but this just baffles me.
There's no crash log, just simply the output I've been getting from the launcher. Either way, it completely freezes at the same point every time. I will link the full debug log in a response to this, but I'm simply going to leave a link to the actual error I'm interested in since I have not got a clue at the moment. The error itself is with the bootstrapper.
Brief introduction to what led up to before, feel free to skip:
Basically, on my attempt at a 200 day survival I downloaded a ton of mods. My latest batch of mods, or a mod in particular has caused an error with the bootstrap that just... doesn't make a lot of sense. The only information I have to go off from is cpw.mods (no idea what it means) and that it probably has something to do with the modlist menu. However, I do not get an error after this and instead the entire application is trying to do SOMETHING but nothing happens. It just locks down.
Here's the error code that does the lock. Interestingly, some code can occur after it, but it is only a small amount of optifine code which has been repeated on occasion before this point.
https://pastebin.com/2A7KS9AL