There was a similar thread here a few months ago, which made me realise how many people I know who have had affairs. I was surprised at the number.
What I’ve come to suspect is that a lot of people are not happy in their marriages but think they they should stay and make the best of it, for many reasons, Then they meet someone, fall in love and after a while they think that they cannot continue in their marriage and that they have to leave to be with the AP, because they cannot face spending the rest of their life in their marriage. Most of the couples that I know in a second marriage seem to have been through a version of this. It’s not the sort of thing you ask people about to a great extent but that’s pretty much what I’ve seen.
People often suggest that if someone isn’t happy in their marriage, they should split first before starting another relationship but I’ve only known that happen when couples are quite young, haven’t been married long and don’t have children.
As for the person below asking if people don’t have any morals “these days”, I’ve read enough history and literature to know that this has always happened. I mean, I don’t regard the collection of documents that currently comprise the Old Testament as any form of contemporaneous evidence, but messy relationships are clearly as old as time,
Before there were central marriage records, it wasn’t unusual for a man to walk out of his marriage and start a new life hundreds of miles away. We’ve always assumed that we can trace our lineage through BMD records but DNA testing is showing us how mistaken that assumption really is.