So, when you say you "cheated", the two of you were dating, right? Did she believe you were in a committed relationship with her? My purpose in asking is to get a better idea of her viewpoint, and if her actions are those of a vindictive nature or not.
She sounds like a WAW who has been terribly hurt by lack of attention, affection, and security. These three areas are very important in a MR. For most women, neglect in these three areas are like a flower not getting sunshine and water. She wilts & dies, emotionally. She feels completely dead and empty on the inside. I have experienced the same thing. My hurt and resentment led to disrespect and then to rebellion and I became wayward. I hope that is not the road your W is going down.
My M was saved, and yours can be saved, too. It will take a lot of hard work from you. Are you ready to push up those sleeves and get with it?
You made a statement about having the M you and your W deserve. Do you have a picture of how it would look? Do you have a picture of how the work looks? It is daily! My grandparents were M over 60 something years. On their golden anniversary I asked my grandmother if she had any advice, and she said you can never reach the point where you stop working on the MR.....if you want a good one. I was still pretty young then and thought that sounded tiring. But guess what? She was so right! No matter how long we live in a M, we have to keep on trying, b/c life changes, and we change b/c of of life's experiences.
You are in a delicate spot. As you have seen, pursuing her doesn't work. Smothering her with conversation and your bodily presence won't work. Therefore, don't talk to her about how you are going to change, don't make promises or discuss your 180's with her. Just talk about here. When you are home, involve yourself a lot more with the children. Play with them, help with homework, help the little one get ready for bed, spend one-on-one with each of them. Put away the games and your phone. Do not spend a long time in a room by yourself. Be an active "presence" in the home, just don't crowd her with it. Make sense?
How overweight are you, at the moment? Are you working out? If not, the LBH's say it is very beneficial healthwise and stresswise. Many of them say they are in the best shape of their lives.
I am going to just throw some things out here, and you can take it for whatever it's worth. I'm not saying you have or have not been guilty of any of these, just making suggestions.
It may be a good time to have a make-over. Polish your appearances with a well-kept haircut & shave, wearing a good aftershave or cologne. Women love it! Make sure your hygiene is great, and look clean & fresh when at home. You don't have to dress up, just be clean looking & smelling. These are important to women. On weekends, don't go around with your hair uncombed or without shaving. Wear a clean pair of jeans and nice t-shirt, if that's your style of clothes. Don't wear shirts that have holes or pants that are going to show a butt crack. Don't go around looking like a slob. If you have a job...say like a mechanic, that keeps your hands in grease/oil a lot......find a really effective hand cleanser and keep those hands and fingernails clean. Nasty looking hands can be a real turnoff to some women.
Pick up after yourself and don't expect the W or kids to do it. Hang up your clothes or put them in a hamper, throw away your own trash, clean up your own messes. Don't ask one of the kids to do it.
If you are in the habit of having one of the kids act as your "go-get-me", (go get me a drink out of frig, go get me a pillow, go get me my shoes, go get me something to eat, etc.) please stop it and start getting your own things. I have seen men do this while laying back watching tv, and it infuriates a lot of women (I am one). Although kids should do some things for parents sometimes.....it can become very obvious to mothers when a overweight, not so active father is running his kids here & there getting things for him, while he's doing nothing. It's not attractive.
If you have any bad habits, this is the time to work hard to correct them. Has your W complained about anything particularly? Make it one of your goals to correct it.
Keep your vehicle clean. Don't throw trash around in it or let it get so dirty someone leaves a message on it. Make sure the yard is litter free and you don't have a lot of old junk, tools, unused equipment, etc. laying around. Toys.... yes, husband's junk....no.
If you holler at the kids, learn how to speak, instruct them, or discipline them without yelling. If you have an unattractive-type of humor, maybe you need to stop if others don't find it funny. If you are loud and boisterous....tone it down. If you are unsociable, learn what to do to be more friendly toward others. Show respect toward others and especially at home. Command respect from your wife & children. Teach the children how to be respectful to their parents, and others.
If you have a lazy nature, you must change it! Even if your W is lazy, too, you must change yourself. Laziness is one habit that seems to be disrespected by the majority of people.
If home repairs or projects have gone unattended for a long time, get on it.
Do things with the kids on weekends.
Do not take over her jobs. Do what you need to do to improve yourself, but don't start doing all the housework, all the cooking, all the laundry, etc. Some H's try to become superhusband, and that's not a good thing. I have not seen one M that type of action has saved!
BTW, do you have a fulltime job?
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!