Turns out he cheated.... HELP

I asked you glow girls a while back on why he was so distant and didn't want to define what we had..  He was with another girl the WHOLE time. And I was the side chick who got put on the back burner. I loved him thru it all. I'm sure you can relate but it HURTS. It hurts my ego too because he made it seem to the girl I was nothing to him. A whole year I was nothing???? I want him back (I sound so stupid) 😩 But I do. Please talk me out of it!!!