The one thing I can't live without is my privacy.. I know, odd answer. But it's true- I think privacy is the most important thing ever, if someone caught me on the toilet I'd have a breakdown. What about you?
Some form of computer - phone, tablet, PC, whatever. It's really hard not being able to look up a recipe or fact check something really quick in conversations or look up drug dosages (through an app instead of going through the entire Merck index).
When we do not count the basic needs for oxygen, water, food and heat, i'd say i can stay without social interactions with loved people.
Currently i really have a hard time but till now i am still able to stay in contact (reallife meetings) since the restriction here aren't that harsh.