RealityStinks,
I'm sorry you are here. I know EXACTLY how you feel right now. I have a somewhat similar story.
You have received excellent advice here. Listen to it.
Now, one thing I want you to be grateful for on this particular Thanksgiving Day is this:
That you DO NOT HAVE CHILDREN WITH THIS WOMAN.
That will make what you need to do far, far, far more easy than if you did - as painful as it is even now without children.
Always keep the following truth seared into your heart, mind and soul:
Her infidelity has NOTHING to do with YOU or YOUR MARRIAGE. Infidelity/Adultery is a PERSONAL failure - not a marital failure.
You have been hurt, lied to, deceived, and betrayed in the ultimate way. Now, let that become anger - righteous, controlled anger.
Consult with a hard-core divorce attorney and FILE FOR DIVORCE - IMMEDIATELY!
EXPOSE, EXPOSE, EXPOSE! Expose this piece of shit affair to the whole fucking world. Tell her family in a somewhat subtle way and let them know you simply don't accept this in your life. They most likely won't support you but who knows - they may - my ex in-laws supported me and are to this day in disbelief over what their daughter did.
Cancel all joint accounts and credit cards.
Gather as much information about the affair as you can and RETAIN that information in a SAFE PLACE that she does not know about. If you can afford to do so, hire a private investigator to track her for two or three days so he can get images, video, etc. No-fault states don't care about the cause when it comes to the actual divorce but if adultery can be proven then it can significantly mitigate any possible alimony she will DEFINITELY go for. Judges don't like boyfriends.
Take on a steely, cold, and determined demeanor. You need to . She did this KNOWING IT WOULD HURT YOU. There is no question. Ask yourself: Are you really in love with someone who could do this to you. ANYONE can do better than this shit.
Do not beg, negotiate or discuss ANYTHING with her.
Acquire and keep a Voice-Activated Recorder on you AT ALL TIMES YOU ARE IN HER PRESENCE. She is on a forbidden-fruit thrill, dopamine-addicted high right now that has driven her to throw away her marriage for a morally-crippled piece of shit that simply preys on broken, easy-kill women.
You are quite young and WILL do better than someone who would do this to you. Imagine if you had children right now. Imagine what there world would be like right now. You don't have children that have to go through this Total Fucking Nightmare.
You simply need to cut this shitbag loose and enjoy your life free of it.