Promises like piecrust

Promise me no promises,
So will I not promise you
Keep we both our liberties,
Never false and never true
Let us hold the die uncast,
Free to come as free to go
For I cannot know your past,
And of mine what can you know?

You, so warm, may once have been
Warmer towards another one
I, so cold, may once have seen
Sunlight, once have felt the sun
Who shall show us if it was
Thus indeed in time of old?
Fades the image from the glass
And the fortune is not told.

If you promised, you might grieve
For los liberty again
If I promised, I believe
I should fret to break the chain.
Let us be the friends we were,
Nothing more but nothing less
Many thrive on frugal fare
Who would perish of excess.