I Do Not Understand

I do not understand
How some people can leave their family
And never look back
To take on a new life at the drop of a hat
But most of all I do not understand
Why people can say they love someone
And then walk out on them
Sometimes on seconds after
Saying I love you
Like those three words to them
Mean goodbye
What I understand most
Is the tragedy
This leaves behind
Family left to pick up
The pieces you left
Behind