I think solo travelling requires a specific type of say introvert personality. As you write, most people are scared of this. And when they do travel without a supporting group, they go... to see friends/family somewhere. I see it so many times around me. People literally rather abandon their dream vacation for a mediocre one with less than ideal companions just to not travel alone.

I am like you too. I am also an introvert. Also I don't travel to rest, but to have as intense experience as possible. Not necessarily only positive, intensity is more important. Often I feel like I need another vacation after a vacation, this time for resting. It is so fulfilling to challenge oneself a bit. There are great life lessons to learn - throw yourself into the trip, without precise plans, and let it unfold on its own.

That said, I just had a son, and I will gladly switch to family-only travel. But all of you, before you reject this form, try it at least once, in some less civilized place. I can recommend India. Just buy a return ticket and some guide book (this part ain't mandatory). You won't forget the experience till your last second on earth. This I can guarantee you.