Need Encouragement - Crashing

I am having an extremely hard time, again, with the CD. It has been 9 months since the worse D&D I could imagine. I let the N come back after a 6 month separation from being together for 7 years. Round 2 lasted 18 months before the last D&D. She only came back because the supply she left for did not work out. I felt this all along but wanted to believe it was because she truly loved me and realized she made a mistake.
I was doing well and on my way but recently I have had a set back to the beginning of the pain. I try to remember the bad things but can only focus on the good times we had. I am lonely, bored and missing her so much. Every minute of our time was adventurous and exciting.
She was on the hunt for new supply one year into our reconciliation. I was being bled dry and she knew I would be out of supply soon. There were even subtle hints from her of what she was up to but I was sick, weak and had a lot of other problems in my life at the time. She promised she would be there for me, help me and she was, just as in the beginning, until one day she came home and said she was leaving. She had secured her new supply the day before and found a house, moved the OW in and began her new life. One day everything was ok (or so I thought) and then the next day, it was over.
She is now living a new fantasy, yes, I know it is a fantasy and will end the same but, I am extremely jealous and I know she does not think of me at all. It hurts so much. I spent 11 years attending to her every need that I lost myself in the process. I don't know who I am anymore. How do I find my strength again and let her go once and for all? It's an addiction I can't seem to break free from.
I seek revenge and I have the ability to cause severe damage but I know it will only come back on me. Does Karma exist? I want to warn the OW, of whom I knew, but I know she would not listen or believe. Yes, I am the crazy, drug addict that used the N and sucked her dry and she could no longer help me as I was only using her, blah, blah, blah.
How do I become indifferent and move on with my life?
Another very difficult thing for me is that i was very close with her daughter. I raised her for 11 years. She has become just like her monther and has D&D me just the same. It hurts, I was always there for her too. I must let this all go, but I don't know how. I torture myself every minute of the day.
Thanks for reading.