You are never alone.  “Alone” is a human concept.  “All One” is of the soul.  All one what?  One Light which emanates from one Source.  All that you know are various expressions, projections of Light.  Could you see without the physical eyes, you would see your interconnectedness.  When you feel alone, dissolve.  Sink down into the heart wherein burns the pilot light that never goes out—your connection to those you love, to Love itself, whether present as matter matters not.  You are so very loved for Love is the very flow of You.