One of the problems here is statistical, as @JonF and @Kara point out. You can't generalize from "one" -- it takes two datapoints to make a line. Stats 101, right?

So given that. Here it is. FWIW.

Because WAW and I are getting along --

-- (okay, she brought a bit of the Batsh*t-Crazy last night, not much, but a bit, and I had to talk her back down off the ledge ["Hey, this isn't working for me -- I'm not supposed to be the reasonable one in this relationship!"] ) --

-- and we're being honest with each other (and each of us obviously really liking that), I just came right out and asked:

So, um, what's up with the change in story these days? Inquiring minds want to know. What makes Walkaway Mrs. SP start thinking that walking-away might not have been the best plan of 'em all?

So statistically non-significant as they are, FWIW, herewith the answers.

Number 1. "You've changed in really positive ways, and I assumed you couldn't or wouldn't. Everything I told everyone you wouldn't do -- you're doing."

Now comes the snippy, "So why couldn't you do that before?" -- but immediately, to her credit, she corrects course: "No, no, no -- sorry, that's not fair. I apologize. I guess the better question is, 'Why didn't I ask you to change before I dumped you? You obviously can.'"

[See? Told you I have the power now. She said, "I apologize." Plain English. No inferring, dodging, weaving. Straight-up apology. That's a 180 for her, by dam!]

Number 2. "I'm angry, and that anger is manifesting itself as jealousy."

Angry about what?

"I asked you to go to counseling for so long. And you just wouldn't. Now you do -- "

-- Hold on, there, sports fan. I started that in October ['08], allegedly three months before you dropped the bomb. So clearly something else was in play. --

" -- Fair enough, okay, but now you're so...smart? I don't know what I mean, exactly, but it's all this 'psychobabble' -- and don't throw that back in my face! I'm throwing it in my own face! You really are, I don't know, smart. Something. About relationships."

Emotional intelligence.

"Yeah, something like that. Anyway, I wish you had that with me."

I was getting there. A lot of what I 'know' now I think I always knew, but I didn't know how to show I knew it.

"Anyway, I'm just projecting my anger on Miss Someone, because I kind of don't want to be angry with you."

That's not fair to Miss Someone, is it?

"No, and I shouldn't be unfair. It's not her fault I did what I did. She's just got good luck."

Number 3. "You seem happy with Miss Someone, and I don't deny that you deserve to be happy, but you seem to have replaced me pretty quickly, which I didn't expect at all."

SP: So what -- you wanted me to be pining away?

"Um, sort of. Sorry. Yeah, I guess. I mean, it made it seem better if you were, like, stuck and I was free. The freedom seemed better, somehow, if I could, like, look back and see you --"

-- Miserable?

" -- Yeah. That sucks, doesn't it?"

(Laughing) Well it ain't too nice.

[NB, more thoughts on this "replacement" concept later today -- fighting the kids' alarm clocks here and they'll be bounding down in moments for "pancake day!".]

Number 4. "I'm afraid you're having better sex with Miss Someone than with me."

SP: Umm, darlin'? I had better sex with Five-Fingers Mary, R.N., than I had with you. You weren't giving it up, remember?

"Oh. Yeah. LOL. Never mind."

So you don't mind that Miss Someone and I are doing the horizontal tango?

"No. [Said very matter-of-factly and, if you know the tonal range of Mrs. SP's voice, in her "total honesty" voice.] Bodies are bodies. Sex is sex. You didn't have it with me, so why not her?"

So what's making you so jealous?

"Two things -- first, you're talking. [NB, see @polly upthread] Which means you have feelings for her. And she has them for you. Signore and I just f*cked, and -- "

-- Sorry for interrupting, but do you wish you had talked to Signore?

"-- No. I don't think so. I mean, you know me. That was so not who I am. That bold I mean. So even though I'm sorry I cheated on you and I'm even sorrier that I've been lying about it all this time, in a weird way I'm sort of happy that I was that bold. That I could be that bold. Do you know what I mean?"

Yeah, I do actually. Anyway, I'm sorry for interrupting.

"And second because Miss Someone is getting the 'good' you, and I had (or thought I had) the dumpable 'bad' you. So you have friendship and sex, and now I don't have either."

You did, but then you turned the switch off on the one and started telling yourself the other wasn't good enough anymore.

"Yeah, I pretty much f*cked everything up."

[And this led to a tangential discussion of our sex life (or, perhaps more accurately, of our lack of a sex life), more of which I will also describe later not for its own sake, but because it gets to the larger issue of how we "write the story" of our marriages.]

So do you still want to get divorced, or do you want to start putting us back together? [SP is a bold mo-fo, ain't he??]

"I don't know. I don't want to be married -- does that hurt you to hear?"

Nah. I get it.

"But the rest? One day at a time, right?"

Right. So am I hearing this correctly? You're sort-of revising the whole 'Divorce is Swell; Freedom -- Yeah, Baby' thing? [said in SP's world-famous Austin Powers voice, which sounds very much like SP's normal voice, though he deludes himself otherwise wink ] but you still believe that there's no more marriage here? That whatever else, we have to not be married?

"Yeah, it's not so swell. I don't know why I thought it would be. Maybe I just wasn't thinking. It just...came out, and then I was, like, committed to it, for my ego's sake. But I don't miss being married, I gotta tell you. Apart from the guilt I feel about the kids, and the sex -- okay, theoretical sex -- I'm actually kind of happy being not-married."

Number 5. "But the real reason is that -- you know, all of my friends? I've sort of come to realize that they're not really as, um, 'supportive' as I assumed."

What do you mean?

"Well, when I told BFF before D-Day, she asked me, 'Are you sure? You better think this through.' And I was all, 'Of course, totally.' But she wasn't. And [Other BFF] totally loves you. Every time we talk she asks why I don't come back to you. And [Other F, whom SP suspected of being the Enabling]? She was disgusted by Signore. If it weren't for this whole situation, she'd marry you. And Former Walkaway/Now Piecing Friend says that anything is possible."

Why is that important? That they approve?

"Because almost all of them are married. So it's not like I'm really going to have this 'single' life. I'll always been the Third Person at the table. And you know me, I need the..."

Validation.

"Yeah. I can live with my own self-doubt, but when the people I count on to totally support me no matter what start to doubt me, then I start thinking that I've really f*cked up."

But you still don't want to be married.

"Yeah, it's confusing. I definitely don't want to be married. But getting divorced sucks."

---------
Those were the answers on the day, any way, and I have every reason to believe they are very nearly mostly kind of accurate. For that day. But at least you get a sense of her internal dialog and, more importantly here, how the DB'ing game plan sort of (might) fit into these situations.