It's a bit incongruous to talk about "all humans" when you haven't experienced them all. Asking for a citation is asking for a justification for this generalization, not for a citation about the experience itself.
I mean, if the argument was "no human I've met can stand being alone for long periods of time", the obvious problem is selection bias: you don't meet people who like being alone.
Talk about straw-man. I never said "no human i've met",you interjected that to make yout argument. I did generalize but you seem to be missing what i was trying to say.
To rephrase: based on my own experiences I don't believe a human can achieve inner peace and happiness without at least some social contact once in a while.
I'm not even arguing with you, let alone constructing a straw man to argue with. I'm simply explaining why an explanation that justifies a belief is appropriate here. I don't care what you believe, I care why you believe it.
I mean, if the argument was "no human I've met can stand being alone for long periods of time", the obvious problem is selection bias: you don't meet people who like being alone.