Lost and Confused

So over a year ago me and my ex wife separated who I have been with for almost 13 years and married for over a year and a half. In our time we bought a house, had 2 dogs. But in the end it came out she was having an emotional affair with a coworker. Which when everything came out I was crushed. So in the end we separated in march of last year. We still talked a couple days a week due to me reaching out trying to make things work because I love her dearly. Which ended in me always being denied. So after the divorce was finalized I still tried to fix our marriage. But the other day I received a phone call from her that ended in a big argument. Her saying that I walked out and if I would’ve stayed and tried this never would’ve happened. Then she proceeded to tell me that she recently started going on dates. I am now crushed and have been since in a downward spiral.

Is there anyone who has experienced this and what can I do to help myself move on and be happy again.