I watched this although I had a vague memory of it, as so little else to watch.
In some ways it was very cliched (would have loved to have had Olivia Coleman meeting up with some random stranger).
I remember finding it a bit cringy first time round but this time round I was more struck by their being a sort of "message". ie have a fling, learn about yourself and become a "better" person and just assume those hurt will just get over it.
ie the male character became a better dad (and attentive husband) and found a job where he wasn't a doormat
and female character, who quite honestly this time round seemed to be in some sort of abusive relationship, verging on coercive control, gets the baby she always wanted but dumps the over the top zealot who is the father for what seemed to be a more conventional "homely" male.
So that's alright then.
(I hope once the daughter had grown up / gone to college the Olivia Coleman characters says, right I've done my being married mother role, now I'm off to see the world, enjoy myself!)