The Reason for the Illusion of Separateness is Companionship.

Are we here to awaken from our illusion of separateness as Thích Nhất Hạnh said? The answer is yes. But the answer is also no. Truth is that the illusion of separateness exists so we, the one, would not be alone and that the reason for all diversity in the world, which is self really, is companionship more commonly known as love.
~ Wald Wassermann