Is it grammatically correct and natural enough?

▪ I cannot survive for even a second without my mom; without her, I cease to exist

Question

Is it grammatically correct and natural enough?

▪ I cannot survive for even a second without my mom; without her, I cease to exist

Answer

I would say, “I would cease to exist”, but it’s natural enough.

Answer

It’s unclear without context, and therefore unnatural. What does ‘cease to exist’ mean? It’s obviously intended to be dramatic, but doesn’t say anything.

Answer

Not sure if it’s natural enough, for me it does sound a bit forced to use without two times in a row.

Answer

Correct, I prefer "could not".