I've just read Crazy Eddie on another thread talking about knowing that he'll be fine if his wife ever did leave.
So, after thinking about what I said up there for a few minutes, I don't think it's a case of me actually 'wanting to leave' - I think it's more to do with me 'knowing that I'll be absolutely fine if I (or my W) did leave'.
A quick, throwaway, and pretty shallow example off the top of my head: I'm quite a friendly/talkative guy at heart, although what happened last year knocked me down a little. I'm getting past that now, and I'm starting to feel a LOT more like *me* again. So... I do all the kids' school runs and get talking to a lot of Mums every day. Several of whom are single. And kinda hot.
Yes, yes, dangerous territory, I know, but I's never let anything happen while I Was married. Trust me. Erm, anyhoo...
Another example is that I'm getting in the water for a surf more often now than at any time in the last 3 years. Yes, I can do that while I'm married, but I could still do it just as much - if not more - if I wasn't.
But essentially, what it all boils down to is that I *know* my life would be OK IF we did eventually split. Or, in other words, I'm realising that it's not my wife who's responsible for my happiness - it's me. Or in other words, I'm getting myself a pretty damned good PMA. And I think that knowing all of this occasionally helps me to take the focus, the headspace, and the pressure off of trying to 'save' us ALL of the time.