This is very difficult and I am in the same place as you. I'll tell you what everyone says to me, make a clean break. It's not easy to let go, but if you know for sure you don't want him back then it's time you move on. Try making new friends or talking a lot to your old friends so you don't fall back into talking to him.
It may be comfortable but that doesn't mean it's the right way to go.

good luck
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Allie
Diagnosed: Generalized Anxiety Disorder & Obsessive Compulsive Disoder. Previous: Borderline Personality Disorder.
I no longer qualify for a diagnosis of Borderline Personality Disorder, but there will always be my borderline traits that I struggle with especially during times of great stress.
I've been working passionately as a therapist since December 2016
