Broken heart? Hmm.

I'm not sure if I've ever had my heart "broken".
What does it even mean to have your heart broken?
What circumstances must it be under or how far must one take something to break someone's heart?
Clearly everyone has different views on this.
Another question, once a heart's broken, can it be fixed?
Does it heal itself on its own over time?

I'd say the closest I've come to either getting a broken heart or just being 'hurt', is the story about my ex.
Haha.