Hi BeyondRage,
I am very sorry for what you are going through at the moment. I know this is probably no consolation, but I think you are handling this incredibly well and wisely.
I think all of our hearts go out to you as you continue to go through that journal. It is incredibly hard, but many thousands of members of this forum (there are more than seventy thousand now) have had to go through the same process, because not knowing feels unbearable.
Although the journal could have been redacted or edited (depending on whether it is digital or ink on paper), you are getting far more truth and openness than many people here have had in a period of years after they discovered their spouse was cheating.
At the moment, you are very much in investigative mode, and that should be your focus, but longer term there are several big issues that will have to be figured out if you choose to stay with your wife.
What happens to her relationship with her open marriage friend and their little group, all of whom must have known what was going on? None of them are friends of your marriage, and they are a bad influence.
Are you going to have to go to every race meeting your wife goes to to make sure she is not continuing her post-race activities, or is she going to stop all future overnight stays and trips without you?
Given the nature of her job, travelling alone and unsupervised, how is she going to assure you that she is not meeting up with men during the day, or inventing bogus appointments?
And one thing I urge you to ask your wife, which is very rarely suggested here, is this:
"You made this mess. How are you going to fix it?"
Now, there is a state of mind that says infidelity cannot be fixed, because the past cannot be undone, and toothpaste cannot be put back in the tube. However, if we accept that rewinding and making it never happen is not an option, I still think it is entirely valid - and positive - to put the ball firmly in the cheating spouse's court and make them come up with a plan and a bunch of things they can do to prove that they are not still cheating, and deserve a second chance.
That is where you can get your wife to come up with ideas that you might not even think of in terms of letting you know where she is and who she is with.
Let her come up with answers for what she is going to do when she sees her affair partners in future, and they try to approach her.
Let her come up with a solution for what to do about her open marriage friend and the toxic influence and impact she has had on your wife and your marriage. Personally, I would not want them within a hundred miles of each other ever again, but it is up to you to make those decisions, and up to your wife if she is prepared to end toxic friendships to prove she is worth receiving a second chance.
This is all down to your wife to fix, and by putting it to her that way, she will buy into it if she really does want that chance.
Obviously, you do not want to be a marital policeman for the rest of your life, but for the time being it would be wise to monitor phone bills, credit card use, location information via Google maps/Find my friends on cell phones, a decent GPS tracker for her car (which she is unaware of), and a VAR for her car, and also one or two in strategic locations in the house where she might make calls when you are not around.
If you want to rattle your wife's confidence about her freedom to be as bad as she likes when you are not around, you could say that while you want to trust her, that is going to take time to return, so there will be times when you will have a private eye watching her. Whether or not you choose to actually use one is entirely up to you, but planting that seed of doubt in her mind may be no bad thing. And it can work for you 24/7, free of charge, even if you never hire a PI for as much as ten minutes.
Another test that can be applied is to have a bouquet of flowers sent to her workplace, with the message, "Why won't you talk to me? I miss you so much", and then see if she tells you straight away, or ever. Hopefully your wife will agree to tell you if any of her affair partners contact her, and tests like this can verify whether she actually means it.
Do those things sound a little cruel, or like a dirty trick? Maybe. However, infidelity is not exactly a loving gift either, and your goal in all of this is to get yourself out of a state of infidelity.
The tools and tactics you employ to achieve that are entirely up to you, and nothing I have suggested is mandatory. Rather, I - and others - will make suggestions to try to give you as wide a range of options from which you can choose and use those that feel right or likely to be effective for you.
In parallel with that, many here can advise you on what to look for in your wife's actions in the coming days, weeks, and months.
A very effective book that many here recommend is "How to Help Your Spouse Heal From Your Affair" by Linda MacDonald. It is a concise guide to a lot of practical steps that a cheating spouse can take after their affair has been discovered. It can be bought in book and audio book form, and can also be found as a free pdf to download.
Both of you need to get STD tests as soon as possible. Do not rely on your wife saying condoms were always used, because there are way too many stories here of betrayed spouses believing that and then finding they have herpes or something worse. Your wife has no idea who else her affair partners were sleeping with, no matter how 'clean' they may appear on their Facebook pages.
Personally speaking, I think it would be wise for you to consult an attorney and get a picture of what divorce would look like. And let your wife know you are doing it. You may not choose to go that route, but it sends a powerful message out that what your wife has done will not just be swept under the rug, or that her position in your life and the marriage is guaranteed, regardless of what she does.
You are not a vindictive man, or a bully, but seriously, throwing a scare into your wife would be no bad thing if you want her to turn her back on cheating as a lifestyle option in future.
If you do choose to try and make it work with her, stress that divorce papers will be served the second there is even a hint of any inappropriate contact with another man. And that when that happens, everyone you know, including your daughters and her employer, will be told the full story.
Let her mull that over.
It does not matter if you would never do that in a thousand years, what matters is that she does not know for sure that you won't.
I apologise if some of this sounds like dirty fighting, but infidelity is a dirty mindset, and sometimes you have to fight fire with fire to destroy the sense of security that makes people think they can cheat and get away with it.
We all feel deeply for you, BR, because we have walked the same road ourselves, and we know how that is. Whatever decisions you make will be respected here, because each of us had to create our own path out of infidelity. There is no magic one-size-fits-all solution that works for everyone.
When these forums work best is when they present you with an array of options, suggestions, and methods, and you pick the ones that you like and bolt them together to create the right solution for you.