I've been travelling on my own for 3 months and I still can't understand most of those questions. But I can say for sure that people, in general, is the most important thing for me.
Even though I was by myself for most of the time, I was never alone. Even though I had no one to talk for most of the time, I was still never alone.
Now I cannot imagine a world without people, they are just fundamental, be it strangers or close friends.
I think the whole life is a search for the answer of that question...
Yeah, I had some long and deep conversations with a French guy about this whole question, we both travel solo trying to think about it - no answear.