Well, mine came back, but then left again a few years later (well she's still living with me, but she's gone emotionally, etc.) - so I'm not sure if that counts. Will she try coming back again? I have no idea. I have a gut feeling she will try someday, but who knows. She complains about everybody's husband these days. Other than her affair partner(s), she seems to be a man hater lately, well at least a husband hater.
Her mom went through an MLC as well, and eventually got back together with her H, but then left again as well (for good that time). My W pretty much blames her father for the whole thing though. She's always complaining about how he left them with hardly anything, etc. I try to stay out of those rants, but she keeps forgetting that her mom left him, not the other way around.
I know of another story where a lady started having an affair with this "bad boy" type guy. She divorced her H, got a bunch of tattoos, etc. and eventually married the OM. That marriage only lasted 9 months, and then she and her original H got back together and I guess are better than ever.
I also think a lot of LBS men get snatched up pretty quickly after divorce by OW - so the opportunity doesn't even exist for their return. It seems like once a year or so, there is a "Dear Abby" article in the newspaper about a woman writing in saying how she had an affair and regrets it to this day and her H won't take them back.