Solost there is so much he did not tell you here and just as we've come to suspect, his version of events neatly avoids much responsibility at all.
How about this version of events? He was introduced to this woman and fancied her. Although he would never have described a male marketing executive as "bolshy and full of himself" he was intrigued by this woman and his reaction to her. What was even more bewildering was that she seemed interested in him too and it had been a long time since anybody but you had found him attractive.
After meeting her, they started exchanging E mails, all on the subterfuge and delusion of creating a profitable new business relationship. He knew he had a happy and stable marriage and perceived no huge threat, but started to enjoy this distraction to the working day. He began to look forward to these interactions and the opportunities to meet.
Because he had absurd notions of female propriety, he was totally wrongfooted when this woman started to make her agenda clear. I'm not sure I believe this story of him buying presents on the plane, but if we give him the benefit of the doubt, instead of telling her how happily married he was, he bought presents and told her that there would be hell to pay at home if he returned back empty-handed.
He got excited about the next trip and there were lots of E mails back and forth about it. It was the most excited he had felt in years, but he felt no guilt about this, because he still didn't think anything would happen unless he initiated it and despite this woman's assertiveness, doubted that she would take matters into her own hands. In his experience, men always made the first move. He refused to think about what he might do if she did....
He spent a lot of that trip chatting to her, until one night he told her that he was going outside for a cigarette, knowing full well that she would soon follow. When she did, she either asked him to come to her room or he offered, but both knew what that meant.
It is absolute fantasy that a week passed with no further contact - it would have been straightaway, to arrange another meeting. And throughout it all, he kept telling himself that he wasn't as much to blame, as she had come on to him. Since that had never happened to him in his adult life, he simply didn't want to take responsibility for engineering it or saying "yes".
He felt like a lovesick teenager in the midst of his first infatuation. He couldn't eat or concentrate and all he lived for was his next fix. This challenged everything he had ever believed about affairs and he refused to countenance that this was just an infatuation on his part. Since there was absolutely nothing wrong with his marriage other than the usual stresses and strains, he couldn't feign marital discord, so decided that since he wasn't the sort of man to have a tawdry affair, these powerful intense feelings must be all-consuming love.
It didn't occur to him that he couldn't possibly love someone he'd known for such a short time and mistook his masculine feelings of sympathy when she told him about her mistreatment by former lovers, as overwhelming protective love. Why, this woman wasn't bolshy at all! She was a poor defenceless woman who needed looking after. World order was restored again and her overt sexual behaviour and asking for what she wanted, could be bargained away by being a bit drunk and lonely. All she needed after all was a good strong man who could take care of her and his view of the world and male and female roles were restored to their rightful place.
He did wonder whether she was simply infatuated and whether she would tire of him more quickly. When it seemed as though she really did have genuine feelings for him and kept asserting that she was "too special" to be just a mistress, he started to feel very stressed and conflicted. He made early promises to leave, but the thought of telling you that and actually doing it, were terrifying.
So he decided that the best thing to do would be to behave so badly and leave so many clues that you would find out and he'd have to leave. He certainly didn't want to take responsibility for making that decision. He imagined that you would throw him out on the spot, or if you didn't, told himself that whatever you said to the contrary, you would never forgive him. He knew with certainty that he would never have been able to forgive you for this after all.
He told the OW a different story however and made out that he sat you down and told you he was leaving.
To be fair, a few nagging doubts had started to creep in about the OW, but he reasoned that he had made his bed and now must lie in it. He told himself that he was doing the most honourable thing by stopping the deceit and that yes, this really must be love, otherwise his strong feelings for this new sexual relationship wouldn't be so close to the surface.
If he had ever spoken to a good friend of his marriage, that person might have pointed out that he was simply infatuated, didn't have much experience of modern single women, was a sucker for a damsel in distress and that his feelings weren't deep at all, just more to the surface because they were new. This person might have asked some questions about the character of a person whose mantra was that she was the victim of dastardly men, but didn't mind if her new man was dastardly to some other poor woman, as long as it wasn't her. Not that he would have talked to anyone like this in the first place and would have got angry and protesting if he had.
I give this 2 years as a maximum Solost.
Now, tell me whether you can accept this version of events, which bits you find difficult to believe and then tell me how you were feeling and when you first started to feel disorientated and as though something wasn't quite "right". Tell me what Christmas was really like in 2009, the month after he had met her. Think only about how you were feeling - were you feeling as upbeat as normal? What were the next few months like, for you?