First of all, I'm sorry this is happening. I'm sure the pain is nothing but excruciating. You have my thoughts and prayers going your way.
Here are some thoughts I have:
1. All you GAL activities are really for you. Do things that make you happier, better, stronger. Try things that require "one-mind", meaning extreme focus, like rock-climbing, boxing or martial arts. They force you to live in the moment and not focus on your situation. Who can really worry about the OM when you are busy blocking your opponent's punch in boxing class? You talk about being a new you. That's great. Make sure it's for you and you children, NOT for you wife. I say this, because the dirty little secret among all of us who were busy doing GAL activities was the hope that the walk away spouse would notice or that the "new me" would attract them back. I also say this because there's a good chance your wife will never come back and your kids will really only have YOU to be their rock and strength. You need to rise to the occasion, but not really for your wife, it's for your family AS IT IS NOW - you and the kids. Your wife has effectively removed her self from your family.
2. You can have some compassion for your wife (the "fog" of the affair, her supposed mid-life crisis) but don't forget that she's acting AGAINST the well-being of your family. She's acting in morally reprehensible manner. She, in classic Biblical language: she is sinning against you and your children. She's acting like a selfish piece of sh*t. This is harming your children. She's modeling a very broken form femininity and motherhood to your kids. What are they learning from this, that's it's OK to abandon your family and screw another man? This leads to my next point.
3. You are an example to your children. What do you want them to see? A strong, resolute father who protects his children and lays clear boundaries to protect himself and them? OR do you want them to see a man gripped in fear who will do everything not to upset his wife so that he feels there's a smooth road paved back for her return? What advice would you give your son or daughter if this were happening to them? My own contemptible passivity during my wife's affair and refusing to deal with it, has scarred my oldest son. He's now dating a woman that treats him like my ex wife treated me. His younger brother actually scolded me once and said, "Dad, you should have thrown her out and had family council telling us exactly what happened any why." I'm offering you advice from my own mistakes.
4. Start taking actions to protect yourself and your children. Face facts: she's left you and she's sleeping with another man. You don't know when OR if she's going to return. It's time to start writing your own destiny instead of reacting to her actions. Let's start with some basics. She offered to sign over her rights to the house to you. Take her up on it IMMEDIATELY. Secure a home for you and your children. When she starts thinking of making a future with the OM, she might want to have the house, and/or significant time with your kids and the OM. Do you want your daughter partially raised by the OM? Do you want her to take the initiative in the divorce and find out YOU have to move out, end up seeing your kids twice a month, while your wife and the OM live in your home with your kids? NEXT important STEP: Go see a divorce attorney. This doesn't mean you are getting a divorce. Find out what are your rights. If you are not ready to divorce, tell him/her that, but ask them, "What actions should I take now to secure my own and my children's safety should I get a divorce?" You may want to start logging evidence of your wife's affair, her date of her moving out of the home, and the amount of time she's spending with the kids (or lack of it).
5. Stop using your in-laws as confidantes. If the affair is public knowledge, don't deny it. But don't reveal too much to them. In the end, they will "circle the wagons" and protect their daughter. This may work against you if there's a divorce.
6. Take a look at the LAST RESORT TECHNIQUE. I think you situation is well-beyond that. You may need to think about the "after the last resort technique" in the Divorce Remedy. You have reached the point where you can't "nice" your wife back in to the marriage. It's time, perhaps for more extreme measures.
7. Your wife is so deep in the affair that she's not really looking at the "new you" and wondering, "What am I losing?". But, she can be made to feel the consequences of her actions by you taking actions that are protecting you and the kids. She will see you pulling away and MAYBE she'll think, "I'm going to lose the house and the kids." That might make her think. But then it may not. People tend to react to the sense of loss or imminent pain.
8. If you get a divorce, you are going to end up setting up some sort of arrangement with your daughter. Your son, as an 18 yr old can not be made to adhere to a court order regarding visitation. Well -- what do YOU want, and what's best for your daughter? Maybe she should see your wife once every other weekend. Start putting this into place now.
9. Even if you your wife sees the new you and wants to come back. You are both going to need counseling and she's going to need to have a serious change of heart and a deep sense of remorse for her actions. If her staying in the family is really only about the new South74 wow-ing her with his new life, eventually you will slip into some old behavior. What then? She goes with OM #2? Your wife lacks a moral compass right now. What will YOU need to be ensured she has grown a conscience before accepting her back into your home. Remember, you are also thinking about the kids.
10. You can't make your wife want to be a good mom again. That's not your job. Act AS IF you are the only sane parent they have. In fact you are the only sane parent they have.
10. Some people would argue there's only one action to take as the SANE parent: Get the rights for the house, and file for a divorce that assumes the kids stay with you. This is for the best interest of your kids. This also, may (even in Divorce Busting theory) be the only thing that actually wakes her up and makes her want to reconsider. Women are attracted to strength and clear intention. A man who knows what he wants, fights for his children and doesn't allow his wife to treat him like cuckold may actually be attractive.
