Good advice above, CT...

One thing you will hear others say is that cheaters lie...

It is also said, If you do not know you are cheating, just ask your spouse...

The point is, he had a secret account that he was using to communicate with someone... regardless of whether that OP was responsive or not... he intentionally hid it from you, so he knows he was doing something "wrong"...

With that in mind, remember what was said above... if he is cheating, he will hide it, so snooping is only pointless as you will find what you are looking for (which won't be good), he will deny it even if you have proof, and he will go further underground with his "secret"...

Take care of yourself... get through these emotions and then start GALing as best you can and become a woman only a fool would leave...