LateNight, I'm going to chime in. I think many people here have given you excellent advice, but it can't hurt to add in a little more. Be forewarned, I am the only girl in my family, I have 3 brothers, and I curse like a sailor. This is all said with love, even if it is harsh.
*A formatting note: if you want to be able to quote from multiple different posts, just open up two browser windows, then use one to browse through the various pages you want to quote from, and use the other for your reply.*
I totally get your impulse to blame yourself. I did it, and sometimes still do when I'm at my lower points. But as much as you are responsible for your actions, she is responsible for hers.
Let's flip this around. I can tell you the story of how my XH had his A. I was incredibly busy with work, but so was my XH. His two daughters lived with us full time, and the general hubbub around raising kids was stressful, of course. We were also trying to get pregnant, so I was doing all of the ovulation testing, temping, keeping a calendar etc. Plus all of my other regular things like grocery shopping, keeping track of all of our finances, booking all of the kids appointments, making lunches everyday, etc.
I had all of the same stressors in my relationship that my husband did. Add in that he is a sex addict, and I've had years of DDays/relapses due to that, I would say the scales are tipped in my favor that I was far more stressed than he is.
I also work in a field that is ripe for cheating. Traveling all of the time, and consistently seeing people in various states of undress. It is well known within my industry that people have "work wives" and "work husbands" and I don't mean the funny coworker you have lunch with sometimes. I have been hit on so many times, by both genders, that I can't even count any more. But no matter what, I always told my husband when that happened. He would always tell me, "I trust you, you don't need to tell me." And I would say, "I know I don't have to, I want to." Social media is almost worse - I get cam girls reaching out to me constantly, at least once a week. I would always screen shot their requests, then text them to my husband and say "Just so you know, I declined this." Because that is the right fucking way to handle that.
You say it's just "human nature." Well I can say with certainty that it's not. Because if ever there was a situation where someone might be predisposed to cheating, it was me, the wife of a sex addict who couldn't stop stealing her panties, and who had such bad ED that it would take hours to have sex. The woman who had access to NSA sex almost daily if she wanted it. The woman who would be gone for weeks at a time for work, and there was literally no way my XH would have EVER found out. And yet, I didn't. It is not "being human." It is the immature, childish way out.
No matter how stressed I was, no matter how much pressure I felt, no matter how angry I was with him, or our daughters, or whatever was going on at that time, I NEVER even thought about cheating. I thought about leaving him, sure. I thought about how my life might be easier without him in it. I thought about how nice it would be to come home and not wonder where I was going to find my underwear. But cheating was never even an option on the table. And when I felt angry with him, or frustrated, or sad about some situation in our lives, I put on my bad-ass-bitch panties, womaned up and had a fucking conversation with him, because that's what adults do.
But real adult conversations and constructive conflict resolution were just too much for poor baby to handle, so he chose to get his dick wet in our bed with some bitch who made it her life's work to tell him how great he was. Your GF chose to avoid conflict with you by fucking her boss (as well as other coworkers, if I recall correctly) - do those sound like the actions of a woman you want to legally tie yourself to?
When a woman has the opportunity to cheat, the potential AP gets sized up against current BF and relationship
The point is, their boundaries have to be fucked to even start sizing anyone up in the first place. You were each playing the game on two completely different playing fields - not to mention that you didn't even know you were playing!
Remember, all the AP had to do was all of the fun stuff - tell her how sexy she is, flirt with her, text and call her all the time, fuck her on demand, maybe buy her some gifts here and there. But it's fantasyland! It's not real! There is no fucking way to keep up that level of sex, romance, interest etc. when you have bills, kids, jobs, responsibilities, household chores, ailing family members, stress, health problems - you know, REAL LIFE!
You also mention the draw of money and job security. You know what else can get you more money, and job security? Doing your fucking job well!
You say if you hadn't let your guard down, if you hadn't become lazy, that maybe she wouldn't have emotionally detached enough to cheat. But she did that all on her own! She could have used that as an opportunity to lean in, to have conversations with you, to express her feelings. She could have taken up a hobby, or seen a therapist. She could have sought advice from friends or family.
She did not have to "take the cookie." She could have told you the second the "cookie" said something inappropriate. Or the time after that, or the time after that. But instead, she chose the A. Over and over, with every text, every sexual encounter, every stolen glance, she chose it. She kept stealing from the cookie jar because she chose to be weak, not because you made her weak.
Bottom line, if she perceived the reward of his penis in her vagina to be greater than the risk of losing you, then her perception was fucked, full stop. Boo fucking hoo, you weren't paying enough attention to her! She's just so damaged, poor her, she deserves pity. Woe is her, she has so many problems with her relationship with you, and she's only human, fallible after all.
Last time I checked, hopping on someone else's dick isn't the way to solve your problems, relationship or otherwise. Did we miss the part where AP has a magical penis that can wash all your troubles away? Can't pay your bills? Got a kid who just won't stop acting up? Got a boyfriend who isn't paying enough attention to you? Just give AP a ride, he'll wave his magic penis and all will be right with the world!
Except that's not how it fucking works. You know it, I know it, and anybody in their right mind knows it. Until she stops believing in supernatural, life-changing genitalia, her perception is still fucked.
I get it. You thought you were going to spend the rest of your life with this person, despite the ups and downs. Trust me, as someone who got married knowing that my XH is a sex addict, I understand that kind of mentality. No matter what, I did not quit, and I can take pride in that. But relationships take two people putting in equal work, and after an A, the cheater has to put in even more so. My XH chose not to put in that work, so I can also take pride in getting my shit and getting the fuck out of there, because I know I'm worth more than that. Do you know that you are worth more than what she is giving you?
Are cheaters irredeemable? No, not all. But so far, your cheater isn't showing any real interest in redeeming herself. You said so yourself, she is fearful, and not making an all out attempt at R. It is NOT your job to assuage her fears, in fact it should be the other way around.
Lay out your requirements for R, then go NC until she meets those requirements. Take up some hobbies. I would say it's way too early to be dating, especially if you're just using it as a ploy to get her attention (which is what it seems like to me, honestly). Get yourself into therapy. She showed you what you were worth to her - nothing she wouldn't mind trading for that mystical genie dick. You need to figure out why you feel that this woman is even worth a moment of your energy after that.