Have you asked her what she wants? When she felt the relationship went down the tubes? How her life could be better?
Did she even feel abandoned when you went out at nights? Was she happy about the situation or wanted more? Is her life fulfilled or is she a housewife when she always dreamed of more?
Are you a grumpy moaning faced shite? Do you sit around eating crap and making a mess? Not noticing stuff? Leaving her to do all the gas bill, car insurance, stuff etc?
Could it be that the minute she gives an inch and kissed you in the past you presumed sex may be available and she wasn’t up for that so said no and you went in a huff? Are there mixed messages?
Has your appearance changed? As in you now weigh twice what you used to, or you’ve stopped caring about your appearance (washing, cleaning teeth, dentist regularly etc)? Or have a beard and she happens to dislike them?
Is she tired or worried about something? Do you ever talk about non-household related things? Do you do stuff together at all?
If you want to get a chance of rekindling your relationship you have to talk. Neither getting defensive. Letting the other speak. Bring honest. If you can’t both do that you will never get to the bottom of this.
It could be that you can’t both do this and putting your daughter first is the priority now. It’s better to have two households with living parents than one where she can sense the tension.
Your wife may feel there is just no coming back and you’re more like brother and sister now but she doesn’t want to downsize into two smaller properties so stays. I don’t personally think that’s a good enough reason. But I understand it. Good luck.