After 18 months of moping after my ex (who I left when I realised he was married) I suddenly feel better....?

Congratulations yes it sounds like your heart is on the mend now. I hope you find true happiness and love one day as you deserve it. As to the wife's reaction to you, far easier for her to lash out at you and blame you. I never understood why women choose to do that other than they cannot face the music of what is really in the lyrics of their song so to speak.