Invisible friend

Walking down the road,
You think you're all alone,
But your senses overload,
You hear a little groan,
No one is around,
You start to panic,
But no need to feel down,
Or even go manic,
They are just your friend,
Don't want to see you sad,
Or to meet your bitter end,
So be glad,
There's an angel,
Looking over you.