Sorry means we affirm something hurt another, whether we really caused it or not (and often it requires acknowledging deep roots in the past.)
Sorry is recognising that the heart has reasons and even though sometimes reason defends the heart, especially the heart that tried its best to love, but possibly sounded out an inaccurate note.
Sorry is an admission that I am human, that I am fallible, that I know at times I can do better. Sorry accepts that at times I act in a way I would prefer in retrospect I did not.
Sorry acknowledges both our humanity and our feeling, it is an attempt to reconnect what may have been torn apart and is in need of acknowledgment, recognition, tender attention or repair.
Sorry should never be the hardest word.