How do we get over the hope of them coming back?

It feels surreal he doesn't love me or care about me anymore. Literally surreal when I look back to him fighting for me, telling me I'm supposed to be his and only his forever.

He left me to pursue another girl. He was drifting from me but I was so in love. He recently got mad at me for mentioning his new girls name to my friend. I said sorry it won't happen again, and all he could say is "Okay, bye". 2 years of love and intimacy just gone..for good. How is that even possible?

How do I get over the hope of him coming back? He won't. But in my head I think "noo..in a month or two he'll realize his loss." He won't!! I tell myself this over and over. He won't come back, yet the hope is still there.