If you really want to speed up this bit you'll need to discipline yourself quite strictly no to dwell on the anger.
I'd do two things.
First every time you're angry, write down how you feel. Keep a journal. Make note of weather, health, what triggered the anger, use lots of words to name how you feel (not just anger but all your feelings good and bad). This can really help you get your head back in control.
Second. Make a list of things to do that are good for you / you're putting off - e.g. gym session, weights based exercise, yoga, walking/running/swimming, rambling, organizing house, filing, cleaning, work projects, art or craft projects, writing, tax prep, bookkeeping, batch cooking, decluttering, meditating, reading, listening to inspiring or relaxing or really interesting podcasts, box set catch up... Put them on a whiteboard somewhere you go past frequently.
After you have raged into your journal go and look at your list and do something on it. Immediately. No thinking and no excuses. Even if it's running up and down the stairs to a podcast for 20 mins.
This trains your brain away from raging and towards caring for yourself. This is an incredibly positive thing to do to take back control of your life. Please try it!
You must refocus on yourself. Focusing on your ex and what he's done will just keep dripping poison into your life. Don't let that continue!