To be honest, I don't believe there are things or people you can't live without. I believe the only things you can't live without (literally) are food and water. I believe you can get used to pretty much anything, and that includes being without the people or the things you love.
That being said, there's plenty of things I like that I'd rather not live without, which include: Coca Cola, pasta, bread, and chocolate (healthy, I know); internet + something to use it (computer, tablet, phone), tv/movies and pen + paper. As for people, I've learned to live without many people I love on a daily basis, living away from home and all, and that is just a part of life.
And just in case you were wondering, that guy I'm kissing up there is A. I lived without him for 25 years, and then some, being on a LDR for the longest time. It's not that I can't live without him. It's just like what Meredith Grey said (told you, TV freak): 'I can live without you, but I don't ever want to.'
What do you think? Is there such a thing as (really) not being able to live without something/someone?
Thanks for reading!