Hi, Stargazer, welcome to PsychCentral (PC).

Accepting one's sadness for a lost or bad relationship and putting some boundaries on it instead of allowing it to be "everything" is the first step. We are more than any one relationship and can choose to deliberately turn from a bad one and start looking toward the future and searching for what/who else we might become interested in while admitting that the relationship was important, learn from and grieve it rather than let it continue to beat on you. It's not part of "You", it's external.