My mum and dad were telling me about who x who'd been married close to 40 years was found out to be cheat, and/or left. You'd expect that with those under the age of 40 and a lot more aged 50 but it is happening to those married for years or living together for years.
Rarely does anyone confess and it is usually being caught out or challenged many times that opens up the door to their dark secrets.
I've had friends and family, usually women saying if they found out that they were being cheated on they leave, kick them out without hesitation. Sadly, come the fact about cheating, the vast majority will get angry and then have a break down or as good as one when their OH leaves. More often than not men come back especially if they are a bit older ie over the age of 40, or 50 being the cases I'm aware of and have a nice home, family, relatives as they get bored with their new lover. Married women that leave their husband/family and stay away for more than a few weeks are often refused a re-entry to family as the family and relatives will side with the man.
The above scenarios are all about people I, may family friends know and work friends stories.
Most find out these days (last 10 years or so) when checking the OH's phone emails. A sure sign of cheating they say is when the man or the woman is glued to their mobile even more than often and get agitated or very angry if you even touch their phone or laptop.
With the older groups, ie over 55, usually a confession dragged out of the culprit and often going on for years, often it is the man that has been cheating on his wife. However, one family we know it was the woman and the husband only found out when he'd got STI.
A word of caution. No matter how strong you think you are and you won't let it happen to you like it possibly happened to a friend/sibling/parent/family etc, come the facts about being cheated on and possibly cheated on and made a fool of for months if not years, you will be devastated when they leave.
Therefore, if you think your OH is up to no good and have the signs of keeping mobile phones close to them, gets angry when you ask or touch their phone/laptop, or ask them why they are going out more often, ask them re new so-called mates, ask about longer work hours, training, away on business, BE PREPARED for the possible bad news and the impact of that. A couple of years ago, tow older ladies at my work place both divorced years ago living alone often talked about workmen coming to their homes and having flings. I challenged one of them and asked where the flings with those that were married or had partners etc and they said yes and I quote "it's not my problem if they fancy me."
TBH, I have asked my husband if he was seeing someone he laughed it off and I hope I was wrong this was a couple of years ago and he does not have any of the traits I refer to and often works from home even before the lock-down but never say never, IMO.
I was going to post this thread and was thinking why did I write this. It's because wheat one of my siblings told me a few days back that made me write this.