It's such a shame you have never "seen" anything like texts or E mails that would give you more information, Catwalker. It means that apart from what your H is saying, you are "unsighted" on the affair build-up period, the event itself and its aftermath.
I could have written your last post at the same stage post discovery-day. My H was saying exactly the same things. The OW came on to him, was offering no-strings sex, he thought it was safe as she was married, he wasn't emotionally involved with her so didn't see it as marriage-threatening, he thought "where's the harm?", the sex was awful....
Your H has probably been brought up on a diet of received wisdom that when a woman is unfaithful, their spouses obsess about the sex - whereas when a man has been unfaithful, his spouse obsesses about the emotions involved. Therefore, on discovery, many men downplay the emotions involved, because they believe that this will hurt their partner more. These are the "well-intentioned lies" I was referring to downthread.
It's a strange thing when a man would rather his wife thought that he was shallow enough to accept no-strings sex, than develop any sort of emotional connection with another woman he's having sex with, but in a nutshell, that's what your H is telling you. Does that fit with the man you know?
It didn't fit with mine - and although it took a while to unpick, it was evident that contrary to what my H was saying (and even believed himself) there was an emotional connection. The day he admitted that if OW had declared her hand when they were first in contact, he would have run a mile, was when we both had a lightbulb moment.
My H needed to be wooed and "chased" - and in the process, needed to feel adored, desired and respected - before he could give himself permission to cross the line. Like your H though, he told himself that he didn't have deep feelings for this woman and regarded it as a bit of escapist fun.
Look, I don't doubt that your H didn't love this woman, or was even in love with her. I don't doubt that she did the running, I don't doubt that the sex was dreadful. I don't doubt that he always loved you and that there was nothing much wrong with your marriage, beyond the usual stresses and strains. Neither should you. Everything your H is telling you is congruent with that.
What I do doubt is that he never had any feelings whatsoever for her, or that he didn't hugely enjoy being wooed, chased and obsessed over.
It might seem from what he's saying about her now, that he had no emotional attachment to her at all, at any time. That's because he's speaking from a position of knowledge about her true personality - no doubt aided and abetted by you being able to point out what a horrible woman she really is. Most men in your H's position go through an "awakening" phase like this when the OW's behaviour is held up to independent scrutiny for the first time - and they "learn" to hate her as much as their spouse does. This is absolutely normal and probably feels necessary to you at the moment, but in reality it's evading how "horrible" your H was too.
There comes a time when you both have to admit that both parties were horrible - to the two betrayed spouses and the DCs involved - and that one doesn't have the monopoly on ghastly behaviour.
You say he "resisted for a while" - that's what my H said - 10 months in his case. But in reality, it was a half-hearted resistance. We both know full well that an emphatic "no, I'm happily married and I'm just not interested" would have caused a permanent retreat on the part of the OW, don't we?
The "resisting" period is in reality, the period that "nice" people need to give themselves the permission to do something they know to be wrong. They also love the feeling of being chased and wooed and what's more, this aids and abets them passing the responsibility for their infidelity over to the OW - she chased me, wouldn't take no for an answer, therefore I can't be blamed as much, can I?
I think it took my H by surprise that I was feeling worse at his account than the truth that there were some feelings involved. But actually, it made far more sense to me, in terms of the person he is - and whom I had known at that point for 26 years - that it had taken more than one explicit text to persuade him to throw away lifelong and cherished fidelity.
If you do believe it's as he says, I'm not surprised that Not Just Friends fails to resonate, but I have a feeling it will one day, so keep dipping into it and re-reading it - both of you. At the very least, given what your H is saying, the chapters on attitudes to fidelity, attachment styles, the story of the marriage etc. still have enormous bearing on your situation.
Forgiving does not mean forgetting - and you are nowhere near that yet, so I wouldn't even be thinking of that at the moment. Even getting on for 2 years down the line, there are still things I have yet to forgive - and I don't put myself under any pressure to do so.
Remember this truth though - we can only forgive when we know what there is to forgive.
I have a feeling that perhaps you and your H suspect that posters' responses on your thread might be delaying your recovery - and that's why you disappear in between posts.
I want to reassure you that although they might bring you some discomfort - and might not be what you want to read - they are written with the best of intentions and with enormous hope and faith in your recovery. You've got a tremendous amount going for you and I think yours will be a marriage that can survive this and get much stronger.
But it's really difficult to do this without help and support from people who have been through it themselves.