Angelica, yes I am saying troubled marriages seem to have better chances initially, from the many posts I have observed, and the more so in marriages that are not that old/long.The leaving and returning seems to be a way of dealing with their problems.
In long term m, if a partner leaves it is not spur of the moment it may be a shock to the spouse left behind but I remember being told when I asked how can they just leave-the answer is they left in their minds long before they physically left so they had already done their grieving over the break up of their m and are much better prepared to walk into the new life.

Yes my m was v happy for prob 28years, but I confess to it growing apart when we became empty nesters, he also was taken over (company) and offered a sideways promotion. Was headhunted and worked away from home in week for 6mths (when I had always moved with him-first clue looking back) and the rest is history as they say.I did all the wrong things, kids shocked and broken hearted(as where all our friends family neigbours colleagues etc)
He once said he would come back and I said only IF he wanted to loved me and not for guilt etc.

He became a g,dad last year and the first person I called was him he then contacted me to ak if his d would let him contact her(in the yrs since he left they have all moved etc so he had no contact details) eventually she said yes so he visited fo 2 hrs earlier this yr and saw his g,son. He said he would be in the country again in a few months and could he bring his mother she said yes(we lost our extended family in break up as well) so far no word.
He has not seen his youngest son in over 8 yrs(son refused to see him in the early days altho his dad never tried really-now he doesn,t know anything about their lives or addresses. He saw my oldest once and ph&email contact couple of yrs ago over my maintenance payments-nothing since.
They knew the OW as I did and because of that they cannot forgive him. He knows that and even admitted to d he wasn't proud of how he behaved and was sorry it had been so long but he feared they would continue to reject him! but he was happy. He never told them or me he had rem-we heard via gossip.
Wow that was long and long time since I posted it all.
Yes it is v sad, but we survived. Sad because as anyone would tell you he was a family man and adored his kids.
We grew up together and I adored him, it nearly cost me my life but my kids have been my salvation-we are v close and now I have a beautiful grandson I love to bits. I forgave my H long time ago but we have spoken a handful of times as my kids do not let me contact him about them but I broke that rule over our firstborn childs first child.