Again...very typical. I know that doesn't mean much when you are living in your own personal hell at the moment, but WWs' As typically end because they are dumped by OM.
Quoted for truth. I have no illusions that my FWW stopped pursuing the other man for good on her own... OM simply stopped responding to her entirely once I exposed to OM's wife. Once OM went a week without talking to FWW, some sunlight crept through the fog and FWW decided a no-contact letter was the right thing to do.
p.s. not that it matters, but how do you know that the OM has a girlfriend and is "in love" with her? Is that a story conconcted by a dishonest wayward wife to throw you off her scent?
Another "Quoted for Truth" item. My at-that-time wayward wife repeatedly told me "It's over" and "there is no affair"... just moments after she got off the phone or IM or email with him.
In a wayward's mind, it can be "over" because the other person broke up with them months earlier, and so there's no affair because what they're doing now is just "friends with benefits". They just have sex. It's just physical now, not emotional.
Or it can be "over" because they stopped having sex months earlier, but still talk to each other and express their feelings for each other. And express that if their spouse and girlfriend weren't in the picture, they'd be with each other again. But it's "over" because now it's just emotional, not physical.
Every wayward will try to justify their decision to keep the other person in their life somehow. EVERY. SINGLE. ONE. Each time using some rationalization to make it OK in their mind.
But it's never OK in the mind of the betrayed spouse.
I think my wife is more obsessed with him than vice versa.
BINGO. My FWW's relationship with the other man was an EA... but looking at the call logs, toward the end she was calling and writing him far more than he did her. She wants to try to keep him in her life because of how she feels when she's around him. It's the addict getting her fix. That's why there has to be no contact for life, because she'll NEVER really get over him while she works with him and sees him daily.
Out of curiosity..is my wife insane or are these typical things a wayward does?
Waywards are insane while they're wayward. Their insane behavior toward the ones they love most is part and parcel of the wayward gig.
The facebook thing seems so small, why not throw me a bone?
Because she's made it clear to you already she wants to hide the affair, and de-friending him on facebook would:
1. Arouse suspicions among her work friends,
2. Lead to embarrassing questions,
3. Eliminate one source of her regular "fix" (remember, you're dealing with an ADDICT!)
Are her denials up to last night typical...what about the anger?
Totally normal.
Telling me she can't keep doing this to the kids (the arguing and crying)
Oh, yeah, my wife really insisted -- and I believe at this point, would still insist, though that feels like it's changing, slowly -- that the post-D-Day "drama" was all my fault. I kept bringing these things up. I kept hounding her about the affair. I kept checking on what she's doing, and my snooping led to our fights.
In my mind, I had to keep reminding myself that these kinds of accusations are wayward fog-babble. Any rational person would agree that a spouse having an affair and refusing to stop it is reason enough for "drama".
Is it possible she lied...
Given your wife's character and proven history of lying to you and others about the affair, what do you think?
...to telling everyone, sending letters, etc.
Why not be honest?
"Until the day you commit to and follow through on no-contact-for-life with the other man, I have no choice but to assume you still have feelings for him and every time you see him it reduces our chances of saving this marriage. I will do whatever I must to save our marriage."
Or just use the last sentence there, which is what I did

...are my chances better than 50/50 my marriage can be saved?
According to Dr. Harley, most marriages attempt to reconcile from an affair, but the way to do it is very, very narrow. If your wife does not stop seeing the other man, your chances of marital recovery are 0%.
Statistically, your chance of divorce is pretty much always 50/50 in the USA. I suspect if you magically eliminated all the known and unknown infidelity from that statistic, however, you'd find the VAST majority of divorces are due to infidelity but get blamed on other things.
if I expose on Thursday, I won't be in town Friday-Sunday....is this a good idea?
I'd say a very bad idea. It's likely one of the reactions your WW will take is to try to force you out of the home or take the kids and move out herself, and if you are already out of town, it's much easier for her to do. Yet that is at war with my "expose everything ASAP" instinct.
EDIT to say: I just realized this is probably a big part of the reason she wants to keep her current employer. She has benefits, she has some stability, and when push comes to shove it gives her the "independence" playing card so that she has the financial ability to leave you and at least somewhat take care of herself.
If you helped her find a new job, it might still preserve her notion of "independence" while satisfying the fundamental requirement for recovery that she stop seeing the OM...
Might be good to get a session with the Harley's on how to deal with this. The opinion of a professional is truly worthwhile. If possible, I'd skip that business trip. Get "sick" or something.