There is something about sad breakup poetry and lyrics that really touch your heart when you are ending a relationship.
This is a beautiful Japanese poem about a broken heart:
I Used Up This Body
I used up this body
longing
for one who does not come,
A deep valley, now,
what once was my heart.
Izumi Shikibu
If you want to read more – check out some other sad or beautiful poems about breaking up.