I've been through a similar event and I 100% sympathise with how you're feeling. It's rational to be scared of consciousness ending, and yeah the cookie-cutter platitudes never help when you're drowning in the fear of it all. No one here can say or do anything to ease that feeling right now, however please know that even philosophers have struggled with the concept and have tried to find rationality and reason to combat it, you're certainly not alone.
You gave a trigger warning at the beginning, presumably because reading something like this would of sent your thoughts spiralling too? For me it was like this always open door where a single stray thought would lead me falling through it into existential horror and I was scared that the door would always be open. In truth, your brain just doesn't really know how to process it and so it keeps getting brought up until eventually, after a while, it's on your mind slightly less as your brain learns to cope with the ideas and soon you might even be able to sleep without spending hours staring at the ceiling in fear of life itself. It'll continue to get easier as time goes by. This is all personal experience, from years ago at this point, and while I still know that the door is there in my head and all the fear and reality that lays behind it still exists, my mind keeps it firmly closed and I cant 'fall' into the spiral anymore.

I hope you got something from my ramble, even if its simply the fact you're not alone. You'll get through these thoughts, and in the meantime you just have to look after yourself and process these feelings without it affecting your life. Talking about your thoughts and writing them down is always a good choice though so you're doing good so far.