Why is he mad at me.

I found out he was talking inappropriately with another female and having her send him inappropriate photos and when I confronted him he flat out tried denying it to me even though I had proof.

Are you two married? You are acting like you have the ranking of a wife. He owes you nothing, marriage means fidelity not boyfriend. Do you have an engagement ring? Why are you acting as if this guy owes you fidelity? Are you under the delusion that a single unmarried man is going to be with one woman? Where do you chicks get this fantasy shit? Lol, He did nothing wrong, you did. You violated his boundaries by going through the phone of a man who is not your husband or fiancée. He owes you nothing. Nothing.. girlfriend just means the chick I bang more than any other chick at his moment. To expect a single unmarried man to give you the fidelity we give our wives is ridiculous. WTF?