At the most fundamental level, all life is connected to all life. All life is a part of all other life. Everything is unified. Yet we choose to have the experience of the illusion of separation. Since being separate is not what is fundamentally actually true, we suffer when we buy into that perspective of separation. When our local perspective or belief does not align with the actual fundamental truth, we experience suffering. Our suffering is a sign that we have embraced the illusion, and forgotten ourselves within it.
Beyond our forgetting, all remains connected. Unity is the underlying truth! This is why Love and Fear are the two great themes of spirituality: Love is inclusive, accepting, unifying; Fear is dividing, rejecting, separating. Love is the move towards What Actually Is; Fear is the move toward the illusion.