Hello Collapsed,
I am so sorry for what you are going through right now. I am proud of your resolve right now, but I want to throw some cautionary wisdom out there.
I, too, had a horrific reveal with way too many details to handle. This drove me to an icy cage of rage for almost a week. I was able to be calm and collected around both my wife and former best friend (the AP), continued to collect the information I needed to file for D, smiled, joked, no one knew any better.
The problem is rage has a shelf life.
I felt like I had been purged with a baptism of fire, and that nothing could possibly hurt me any more, but I was very, very wrong.
My concern for you is that you have already indicated thoughts of self harm (I would venture that almost all of us BS have, this is unfortunately part of the amazing gift of infidelity), I would plead with you to make sure you are in extensive individual counselling, multiple times a week, immediately. This was indispensible for me.
Also, make sure to be calm, always. If you cannot be, detach, leave if necessary until you are calm. The suggestion of a VAR is an absolute must. If it is legal in your state, get an automatic call recording app for your phone conversations. Email instead of text.
I never ever would have thought my wife was capable of the level of manipulations and accusations she threw out after DDay, nor did anyone else who has ever known her. But like your wife, she exhibited no remorse, and she would be damned if she was going to be accountable for her actions. She is going to rewrite your marital history to make herself as victimized as possible to rationalize her affair, and this may go on forever.
In my case, she would keep a VAR, and then bait a reaction out of me (like mocking me sexually compared to AP), over and over, hoping to get a vicious reaction, something to be able to use for custody leverage, all recordings done without my knowledge. This occurred while she stated that she was committed to Reconciliation! Be prepared to protect yourself and your children, and trust virtually nothing she says.
This is no longer a marriage, or even a relationship, your wife killed those. If she was erupting with regret (and eventually real remorse), AND you were both committed enough to each other to be willing to endure years of hell for the reconcilliation process, then I might advise differently. But this sounds like war.
In war, give nothing of your position. Do not make threats, avoid conversations that are not perfunctory living and coparenting arrangements. Implement the hard 180 for your well being.
She does not need to know anything about you, your plans, your thoughts. Threats (like going to HR) are unnecessary, because they would only be useful if you were trying to elicit a response towards breaking up the affair, which is not a path I would recommend, as it will escalate her level of perceived threat from you, and she will respond accordingly. She lost the right to knowledge of your intentions when she destroyed your family. Realistically, anything you give her would be used and twisted against you as long as her emotional committment is still to him.
Wishing you strength and patience. You will get through this. Keep posting.