AIBU to not tell my mum about cheating dad?

There is a thing called Wilful Ignorance. It means you keep your head in the sand. Don't ask, don't tell. Maybe your mum has adopted that attitude. If you do tell her, what is she actually going to DO with that information? Divorce & start again in her 60's? Telling her might not change the outcome, she may stay married, but it will hurt her!

I wouldn’t tell your mum straight away, no. I’d spend time with her. But I’d pretty much always keep my nose out of other people’s relationships.

Giving my point of view
isn't that what a forums for getting a wide range of experience,info and opinions

you don’t have to agree or disagree just be adult enough to respect and recognise other people have different views and opinions

So you have no basis for claiming most women know about affairs and turn a blind eye to them, but youre more than happy to push that narrative anyway, and by doing so, encouraging women to keep cheating mens secrets for them, on a website for women to support women. Amazing.

You are not protecting her, you are just contributing to the deceit and removing all choice from her. You’ve no idea if this has happened before and if their marriage has been happy, you don’t know if he’s actually cheating, if he plans to leave your mum for her, or anything really. And messaging the woman while your mum is in the dark is just treating your mum like an idiot. Either tell her, or stay well out of it.

you’d rather your child keep the worry to themselves and then have to live with the uncertainty about whether or not they should have said something, just to avoid a bit of potential awkwardness? That seems very odd and emotionally immature to me.

As I said, I’ve been where OP is. If it transpired that my mum had actually known about the affair, I’m sure she’d have probably said something like “okay thanks for telling me, I’ll deal with it, you don’t need to worry about it anymore” because she’s a grown woman capable of adult communication. Why would she have to lie or defend anything?

Mostly though, I know my mum would never want me to have the shoulder the burden of carrying (or even just, in your scenario, believing I was carrying) a secret.

Let’s just agree to disagree

thats the position my mum was in

there’s a world of difference form typing advice from a keyboard that will never affect you to the practicality of having to personally implement it

I would definitely speak to your dad first. You know your mother better than any of us do. We can say "I would want to know if my husband was cheating " or "I have been married for 40 years and dread the idea of starting over on my own" but that's our experience not hers.

Many years ago, when I was an adolescent, I went home to find my father had another woman in the house, in the bedroom. My mother had gone off to visit DGM for a few days. I didn't tell her when she came home, and I don't regret not having done so. My DPs had another 20 years of what appeared to be a happy marriage before my DF died. I could have blown that apart and destroyed my mother's life. Who knows, maybe she already knew and was pretending not to.

Where's your evidence for this claim?

I would talk to your dad.

Nobody’s defending him
the majority of of people know about partner’s affairs
and a lot of the time they can cope if they think no one knows
at 60 rebuilding her life and housing herself are slim

I would tell your mother what you actually know and let her draw her own conclusions.

If it’s “not what it looks like” as your father says, then there’s nothing to hide.

I do think you should stop inserting yourself and your DP though. I don’t know what you thought you would gain by messaging the woman.

At this point, you’ve meddled so much that not telling your DM would make her feel like an absolute mug that she was the only one not to know and everyone else was discussing it, when it inevitably all comes out.

If your Mum finds out about the affair and that you knew and did not tell her, your relationship will be very damaged.

I think you should tell her.

God why do so many women leap to this defense for cheating men? If she knows, there's no issue with op mentioning it, but the chances of that are incredibly low.

Awful situation, but I would tell your mum. If it ever comes out that you knew and didn’t tell her, you risk her feeling like she’s been betrayed by her husband AND her daughter.

Perhaps your mother knows and is still happy with her lot if she no longer loves her DH

I’d think that one of your parents having an affair behind your other parent’s back IS your business?!

You cannot control two adults who want to to have an affair.
Telling them off will have zero impact
Telll your mum what you know so she can decide her actions.

This. Let them sort it out.

I don't envy you OP, what awful situation. Your mum being ill has likely fuelled this, plenty of research showing how men leave sick partners. Personally, I'd tell mum because to not tell her would be me going along with their deception. And I couldn't have done that to my mum, BUT I loathed my dad, so I wouldn't have felt any split loyalties.

It also occurs to me @Cutie18327that you mention your mum has been unwell. Any nurse will tell you that men flee women when they get sick. It’s always sisters and daughters and friends on the chemo ward with women, while wives dutifully come along. Women are least likely to file for divorce in the year after their husband’s serious illness, but men are most likely to file for divorce at this point. I think you need to prepare your mum (and yourself) for the potential that she’s going to be abandoned while unwell.

But this is also a very good point. I still couldn’t pretend though.

This isn’t a random acquaintance. You can’t just rid yourself of that knowledge about your parents. She’d basically be lying to them, and herself, for the rest of her life. Be serious.

OP, I would personally tell my dad that he had until x date to tell the mother or I would. If you’re the one to tell her he might manage to convince her that you’re lying and drive a wedge between you.

The fact you and your Dh have made your dad and the woman aware you know and there not panicking is quite telling
Keep out of it
my guess is your parents marriage has been on it’s arse for years but the rub along in some sort of fashion

wouldn’t be surprised in the slightest if your mum knew already and turns a blind eye to eye . As long as nobody knows
YOU NEVER KOWN the complexity of people’s lives

from your mums point of view how easy would it be to start again
could she house herself and what about pension even if she got 1/2 yours dads if he’s got one her finical security is poor in retirement
people often settle for the least worst option

these are the practical implications of dropping a grenade in your mums life