Off of reality...observation and experience. Because there's no one who truly likes to be alone. Just people who don't know know how to form or keep a relationship...and those too afraid to try. It can be...a really scary thing. Because losing something or someone important to you can hurt...and be one of the most frightening and devastating feelings...
It's a lot easier to watch from the outside than to actually participate. But then the person simply watching...misses out on experiencing anything at all.