Even at nearly 40 years old I am still drinking 8+ cans of diet coke a day.
That much coke is not good for your body. You should not drink that much.
I'm afraid of actually trying to change anything in my life and turning 40.
Sounds like you are addicted to diet coke! You need to seek addiction therapy if you can't stop yourself from drinking that much coke in a day. The health risk is huge!
Maybe, I've read the science before and it said it was fine
You should at least try seeking help for drinking so many cans of coke per day, diet or not. That's so much to put into your system and it can't be good for you.