Train, I thought that I already posted something like this, but it may have been to someone else. Lets put aside DB for a minute. Men are often encouraged to FIGHT for their marriage- to compete for their wife's love. Like it or not, we're programmed as men to pursue a mate, women are programmed to respond. Therefore, a pursuing woman is not percieved to be "attractive" to a man. While wives tend to respond to a husband that changes his ways, the same cannot be said (in general) for a WAH. Men are likely to return only when their options are shot.
Additionally, in your case, this isn't your H's first affair. You cannot treat this situation as if it was a first affair that he just found himself in (ie: he started having feelings for a female work friend vs actually LOOKING for an affair). Your H was a predator in this case. He sought this woman's attention, asked for her number and pursued her. You think you can change someone wired like that by being a tad less critical to him at home?! *cough* *cough* Me neither.
Starsky (or choc, or pup- no I'M confused ) was fighting a different situation than you are. Look at the commonalities, not the differences, in his approach. A plan of action, boundaries, 180's, no "pursuit". Take your lessons from there.
Your husband deserves to get his butt kicked. He has a way of looking at life in a very selfish way. He gets what he wants, who cares who gets hurt in the process. For some reason certain women are drawn into men like that. Perhaps it's some sort of urge to be the one that changes them? Who knows. I can tell you, however, that unless he has a mind to change the way he approaches the world he will always be the same jerk that abandoned you. Changing yourself to somehow re-attract a man that abandoned you twice? Who will you have to become to maintain his interest? Is it even possible? Tough questions....
Wait!.... I have one more 2x4 in the 'ole tool box!
Please be very careful hanging out with a married man- that's how affairs begin. You don't have to be looking for it, it just happens. Sneaks up on you, if you will. Teaching someone something new, especially with an element of danger, can be quite the aphrodisiac.... Maybe you have no interest, but that doesn't mean that it might not mess up HIS head and affect HIS marriage.
I hope you don't take what I wrote as hurtful- that's not my intent.