STOP trying to change someone who doesn't want to be changed.  Stop giving second and third chances to someone who continues to abuse your forgiveness.  Stop tying to make something work that will NEVER work in a million years.  Walk away and don't look back.

A relationship, job, friendship, whatever the situation, if it doesn't fit YOU, leave it behind.  Stop wasting your time trying to fit a square peg in a round hole.  Very seldom do people change, it does happen, but not often.  And many times, if a person shows change, it's only short lived.

Stop walking back to the place where your heart ran from.  "Oh but it'll be different this time", will it?  If you are in a situation that doesn't fit you, instead of trying to change the situation, change your placement in the situation and remove yourself from it.