Infidelity Support Group
Any relationship in which one partner engages willfully in sexual relations with another outside of the partnership is considered to have experienced infidelity. This breach of trust is often traumatizing for the faithful partner as well as the relationship, and support is often needed to heal emotionally and to decide whether or not the relationship should continue after...

When she started bitching about him not taking out the trash or picking up his underware off the floor.. he will realize WTF did I do.
Everyone is on their best behavior when they are having affairs.
Call a lawyer and get your things in order. He still has to keep up his financial obligations. I would make sure you get all that in writing.
I know what you are going through, except my H begged for forgiveness.
Marriagebuilders.com helped me get through ... they have some helpful books
Good luck
My H did the same thing - he started up with a co-worker at the same age.
It's pathetic.
It's an affair so, of course, things are wonderful. Reality will set in.
Document everything, out him at work. Do what you need to do to take care of you!
Take care of yourself and your family by getting a lawyer and making it quick and easy.
Like others have said, he will be more miserable soon enough.
Affair based relationships end in train wrecks 9+/10 times.
Then they look back at the happy family that has moved on without him. That is when the soul crushing realization comes.
"Be the best, sweetest, strongest wife you can be right now"
act in alignment with principles that you believe in
I'd imagine that you were a sweet wife and that he chose to be be a crappy husband and put you, his marriage, & his family at risk
get tested for stds
get yourself counseling
get a lawyer
prepare for the coming storm
maybe he will wake up and want to mend things
that is not likely
and even if he does try it is most likely beyond his cowardly reach
[the next is from the marriage builders website]
So one of the most important reasons for a spouse, particularly a wife, to go from plan A to plan B is to protect herself from the physical effects of long-term and intense stress.
Plan B is to avoid all contact with the unfaithful spouse until the affair has completely ended and the wayward spouse has agreed to my plan for recovery. In many cases, once an affair has ended, a betrayed spouse makes the mistake of taking the wayward spouse back before an agreement is made regarding marital recovery. This leads to a return to all the conditions that made the affair possible -- love is not restored, resentment is not overcome, and there is a very great risk for another affair. Without agreement and subsequent implementation of a plan for recovery, the betrayed spouse is better off continuing with plan B.
https://www.marriagebuilders.com/graphic/mbi8113_ab.html
I think many BSes are shocked when they believe their are excellent spouses and the CS then goes and betrays them.
This surprise is due in part regarding the believe that your good actions toward your spouse are transactional and stored in a bank from which you build credit and can withdraw from.
The truth is that you can be the best spouse and be treated like trash, or treat your spouse like trash and still be treated like a king/queen.
There are no enforceable rules or consequences in place for relationships. It is like the wild west as even society/media itself often enables and perpetuates acceptance of poor behavior.
Cheating is 50/50 between men and women nowadays. Often times both cheaters are married anyways.
Exchange the "women" with "men", read it, and tell me how that makes you feel.
Also remember that at the end of every affair there has to be another woman or man participating in the affair with your spouse.
1) you get the whole house to yourself with no one to tell you to clean up
2) no fighting over what to eat or watch on tv
3) you can finally go do whatever you’ve always wanted to do
4) you can start meeting new people and enjoy doing it while collecting spousal support
Make sure to never catch him seeing you anything less than happy. Make sure to always show him what he lost.