The sign for "lonely" uses an index finger. If you are right
handed, your palm is facing to your left. The index finger is brought near to the lips and then slides down, forward, up, back,
and down. Do two complete (but small) circles.
YOU SOMETIMES FEEL LONELY YOU? (Do you sometimes feel lonely?)
Here's a sign that means "by myself," "only me," "I was alone,"
"I was the only one."