I do understand how deep of a hurt that must be. Betrayal is a hard thing to work through.
Their relationship is based on betrayal as they are both cheaters. While it may appear that she is enjoying what "should" have been your life, don't be so sure. He cheated on you and who's to say he isn't cheating on her.
The fact that she tries to out do you in everything tells me she is very insecure and is jealous of you.
You know the old saying "Jealousy is the highest form of flattery"
I truly encourage you to let go of your anger as it only hurts you. Do not give them power over your emotions. They can no longer hurt you unless you allow them to.
You have the opportunity to write your own new story. Do things that will bring you joy and fulfill your life.
Leave the betrayers to each other.
((HUGS)) to you......
