Yeah, the lies are part of it. An affair in itself is a pretty damned big lie, so is it any surprise that they cover a big lie with smaller ones? And when caught they'll craft some amazingly intricate lies to make the LBS sound like the crazy one. It's all part of the script.
Julie, based on what you posted there's not really much of a doubt that he's in an A. So my question to you is this, is it a deal-killer? Are you still standing for your M or are you ready to walk? Take time to think about that, it's a huge decision. In my sitch I never have found out the extent of my W's affair. Early on I really struggled with not knowing if it was a PA or EA. Finally I asked myself what it would take to get past this, and I decided that knowing would help. But I didn't have any evidence and I didn't want to snoop, so I decided then that I would assume the worst. My W was involved in a PA. Then my decision was where to go from there. It took me about 2 weeks to decide that I still wanted to stand.
Now I am NOT telling you to let him off the hook for the affair, nor am I telling you to be a doormat. If you decide to stand, that just means you're not closing the door on the M. You still MUST detach, GAL and leave him to the mess he's made.