Solitude is nice. One who enjoys it the most is the loner. But his journey should not be despised. He has what many carve. Self-dependence. But there are two sides to every coin and one has to experience that in life.
You may think you value your aloneness without being lonely, but you still get used to being around people with time. That time you miss solitude. But when those people go away, suddenly the aloneness that was dear to you becomes loneliness.
The worst kind of loneliness occurs when surrounded by people. But sometimes even that seems better than not having people around you. Living souls are comforting to have as a part of the environment. They don't eliminate your loneliness but they make it less creepy. Yet sometimes they aggravate the situation. They don't understand lonely don't want to be pitied. The only way this helps is you realise you enjoy your solitude more than such favours.
From aloneness to loneliness and back to aloneness. It's a vicious circle.