The human heart is the Divine throne room. Break a human heart and it is quite possible that it will never mend. Break a human heart and you disfigure the place that the Creator Himself has created in order to make known His names and attributes.
Break a human heart and you risk turning that throne room into a tomb full of regrets and broken wishes. Break a human heart and you will be responsible for what happens to that heart afterwards.
Break a human heart and, unless you repent and somehow make amends to that heart, you risk being locked out of heaven until that damage has been accounted for and put right.
Do not break a human heart if you yourself do not wish to be broken.