Is porn considered cheating?

I told my before when we started dating a other times that I consider porn as cheating because your getting off to a girl that is not your significant other. He agreed and said yes I’d never watch porn and I never will. Well today I wanted to look up a song on his phone and saw “girls do porn” and I was disgusted. Now he cheated on me for the first 3 months we dated so seeing this really broke my heart.. we had a horrible argument and I told him I was breaking up with him and he started balling and saying that we didn’t have sex for 3 weeks and he was bored and just had the urge to do it and said he felt bad and didn’t even finish. But I can’t get the thought of him jerking off to another girl out of my mind and it’s eating me up idk what to do. I can’t even look at him the same anymore but I love him to death.