Listen, man, you say you feel like an idiot monitoring her... I get that. But its already telling you things about her that are surprizing you. My WW didnt talk much in her car either. Because she did all her talking face to face or on hidden apps or texts.
My wife & I are both professionals. She is higher educated (two degrees vs. my one) She travels for work as well like your wife does. I caught her in a well-hidden affair with her boss. She gaslighted me and lied her ass off until it was undeniable.
See, here's the thing. You two have your life at home, and then you have another life at work. Listen to me very carefully. She likely spends MORE time with some of those coworkers than she does you. Think about it- sit down and do the math- counting sleep hours etc... Do you really think shes not going to befriend these people? Now, the other thing is this- out of those people, how many are men, and would like to get in her pants? My WW and OM hid it VERY well from everybody.
What kind of office is it? My workplace was almost all men- and we worked on highly technical stuff with hard deadlines (think engineering projects). My wife's office on the other hand is more people oriented stuff. They network. They go out to eat lunch every day. When traveling, a lot of it is just seminars and conferences. When traveling, the coworkers eat meals at nice restaurants and visit bars for drinks after supper. The conferences have 'socials', perks, and activities planned for attendees. Its a perfect storm for breeding affairs, and that crap ought not to be allowed. The temptation is there- and it is very strong. They get too accustomed to it, and next thing they are in trouble.
Her traveling for work is like an adult vacation with no kids in sight. ok? Now what bad could possibly happen when her [B]boss decides he wants to get in her pants and starts 'working on her'? He's her boss- he makes the decisions. He makes a pile of money. He's the alpha rooster in the henhouse. What happens when he starts giving her the right kind of attention? You start looking like a chump to her- that's what happens. It happens so frequently that I believe its almost inevititable.
After I caught her, I bluffed a full confession out of her. My wifes affair started by her working too closely with this guy. Eating lunch with him every day, riding in cars with him, staying late to finish stuff up. He worked on her with game, persued her relentlessly. She confided marital issues with him about our relationship where he convinced her to see me in a negative light. That progressed to a kiss in the office afterhours. Next trip they took, the guy wined and dined her and invited himself to watch TV in her room- and my wife became an adulterer. They started by only getting together on those trips- then it progressed to vehicles and behind locked doors in the office several times a week.
I had no clue whatsoever until more than eight months later she became too complacent about texting with him and I began to get suspicious. She had been screwing him for that long, and acting at home like she always had. It was a masterful performance.
I'm just telling you to lay low until you know for sure WTF is going on. Don't confront. Dont act weird. Just fake it. Keep monitoring religiously. Dont get caught! If you can afford a PI, hire one. When you are on your trip- have multiple vars placed strategically. Keep it up until you catch her, or else you are SURE there's nothing going on.
Where you dont want to be is in limbo several years from now with a suspected cheater that has learned how to play the game and not get caught- which is where you will be if you dont catch her and have solid evidence. Evidence gives you leverage- divorce or reconcile- if you have evidence you can make informed decisions and she can't deny it, lie to family and friends, and rewrite history. Knowing what I know now, your wifes actions bear investigation. Chill out, lay low, catch her, get the evidence!
Forgive my thread jack but if you, or anyone else for that matter, can read the bolded above and see intelligence then we have vastly differing definitions of what constitutes intelligence. What I see is immaturity, lack of self respect, one who is unsure of herself, her life, her feelings and pretty much everything she thinks she knows, one easily manipulated and sadly lacking in integrity, a person of poor moral character, in other words a young teenage girl. A girl who has not yet developed sufficient intellect to be able to see through her "boss" like a looking glass, understand her place as wife and mother, understand honor and integrity, truly know who she is and why and have a good moral compass.
If she were truly intelligent this would not be happening to you now. Intelligent people do things out of reason and logic and with rationale and if she were such, you could simply express your concerns, ask for her explanation and get a reasonable response. The fact that you cannot is very telling and forces you to sleuth around to find the truth.
You must remember the mentality you are dealing with and treat her accordingly.