According to Osho, joy in aloneness appears when you stop borrowing consolations and meanings to avoid loneliness. Religions and beliefs were props to escape emptiness; maturity is to drop them and face life's meaninglessness directly. Truth stands on its own feet: when you no longer demand meaning or company, aloneness becomes your own space - not fear - and a quiet, self-sustaining joy arises.
Let go of make-believe comforts and just be with yourself; when you stop chasing reasons and company, being alone starts to feel peaceful and friendly.