another thing my therapist taught me, was the drama triangle. in a painful situation, usually everyone takes one of three roles:
- Victim
- Persecutor
- Rescuer.
If one person switches roles, it forces the other person into another role, causing more pain just of a different flavour.
your ex was a persecutor and you probably tried to rescue him for ages, but finally you were forced into victim role. eventually you were like, FUCK THIS, and became angry, moving into persecutor role. predictably, he then had to vacate the role of persecutor... hence him coming to his senses and stopping it all. he moved into rescuer instead, meeting up with you to give you what you needed to "move on".
which was a relief to you for a little while.
but you stayed stuck in persecutor role. hence revenge fantasies, where you persecuted HIM, taking over your like.
again, same level of pain, just a different type to when you were the victim.
and all the drama continues to play out in your head. you constantly move around the triangle, remembering painful things, recalling past roles (his and yours), etc.
the way to stop the pain is to resist the temptation to just switch roles again. one thinks this will help, but it won't. pride keeps us in the triangle usually - you don't want to opt out of it because on some level, you feel that's admitting that the bad things the other person did were actually OK. BUT, that's not what opting out means. it simply means you are doing the only thing that will really stop the pain.
basically saying, "there is game being played here inside my head, and it hurts to play, so i am just going to do something else. like knitting. or laughing with my new partner."
it's the old "do you want to be "right", or do you want to be happy?" thing.
if you can become aware of how you use the drama triangle to continue drama, you might be able to start opting out of it, little by little. you'll feel your pride being hurt as you do it, but that's momentary, and you're rewarded by an enormous reduction in pain.
good luck.