I dumped him but he won't back off

MY ex-partner will not accept that our relationship is over.

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I dumped him a few weeks ago because he kept sexting other women right under my nose. I'd had enough. What can I say?

I got sick of catching him, on his phone to love rivals.

We'd been together for three years, but I'd walk in a room, and he'd jump out of his skin with a guilty look on his face.

I'd attempt to snatch his phone out of his hand, and he'd go into a toddler-level meltdown.

Things came to ahead on the night of his birthday. I was pleasuring him orally (for a treat) and his phone rang. I growled; "Leave it" and he took the call anyway. It was a woman he used to date a few years before me. I could hear her whispering rude words and hit the roof. I stomped off to the sofa and ended our relationship right there and then.