For me the difficulty in letting go of the "addiction" was that it would force me to face myself and my own issues. Why was I so willing to accept poor treatment? Why was I so sure that what I wanted for that person was "better" than what they wanted for themselves? Why was I so anxious to save someone else, usually at the expense of my own wellness? Why didn't I feel I deserved the energy and time and attention I was so willing to throw down a black hole of someone who was hell bent on ignoring their own issues?
There's no magic pill.
Acceptance is the only answer. Remember that pain is inevitable, but suffering is optional. You know the sayings, sure, but believing them is what it takes to overcome your addiction.