Did his mother tell you he wanted pictures of her? If not, what you're getting is his take on it. He's lied to you, why wouldn't he lie to the OW as well? Or are you saying that you read an e-mail from his mom that asked for those pics? If so then sorry, that's my mistake I misunderstood.
Glad to hear you've got a good attorney, you'll need someone in your corner. Take some time though and get your thoughts together, consult your attorney, get a game plan...then proceed.
You definitely need to have a clear head for the next step.
