Never getting it how?

People come and go,
But who they would be you’ll never know
This is so worn,
I feel the thirst when you
're gone
Didn’t mind when you said, "it will be good for us both"
But may be not for my growth
Don’t crave for you anymore now,
Cause' it just bothered me and not you anyhow
God, bless people who break hearts,
Cause' it is not less than an art
Don’t know what happens to this four chambered thing, 
Always lets a person get in, when it hurts like it stings
Ventricles colapse, auricles shrink, 
This happens just in a wink
Best feeling that is what people call it,
Deathly living that is what I got it 
Precious is this pain, 
But there is never a gain
All those stories of love, 
They are just gone above
Worth will it be? 
If you have to question it, be free
Maybe you’ll not understand this now,
Well even I don’t get it how? 
Difficult it is to see it this way,
But they just don’t know to stay.