Heart of my World

I understand so little in my world,
not least of all the workings of my heart.
But as I sit and hold a woven bookmark,
(a simple token from a passing love),
my heart transcends its lot of pumping plasma,
and fills my veins with memories long lost.
The blood it pumps begins to carry sorrow,
each beat it gives weighs heavy on my soul.
How many beats since I last felt the sunshine?
How many beats before I leave the cold?