AIBU not to want to meet my uncle's affair partner?

Quelle surprise, an entitled man continues to behave in an entitled way!

It's up to you. I think it would be more reasonable to refuse to socialise with your uncle. He's the one who lied to you etc. If he's okay to socialise with, blanking the OW seems somewhat misogynistic.

Good on you OP. Your DU could easily have given your DA some dignity in ending that relationship before starting another let alone lying to you all to boot. He’s still your DU but she clearly wants her feet under the family table but you are well within your rights to stand firm, stand by your DA and tell the pair of them bed/lie in it.

It is not her fault. She made no promises to your aunt, your uncle did. Why are you punishing a stranger but not your uncle who lied to you and treated your aunt badly? I find this type of attitude misogynist.

It is not so strange that people also direct blame at OW -not only at the OW, but also. So, she didn't make and break vows to OP's DAunt. But she still did a shitty thing; everyone knows that affairs are unkind and harmful, culturally it is part of our social contract. So it is entirely reasonable to have an expectation of both men and women not to participate in affairs. It is also reasonable to make certain negative assumptions about a person's character once you know they knowingly pursued a romantic relationship with a person already in a relationship: callous, selfish, impulsive and lacking in empathy. People who have affairs indulge in a special kind of nasty, irrespective of whether they were themselves in a relationship at the time or not.
The woman who crunched my bumper in the Sainsbury carpark before coolly driving off -she'd not made me any vows of any kind either, but I still absolutely blame her for the damage she caused. We are not unreasonable when we expect people not to be dicks, are we?
So OP, I absolutely understand why you don't want to meet your uncle's partner. I hope your aunt is recovering.

Misogynistic but also so much easier blame and punish the stranger rather than the family member. Punishing the family member would require more disruption to one’s life, more uncomfortable situations and potentially missing out on events and gatherings, whereas one can loftily proclaim one’s utter disdain for the stranger involved without actually impacting day to day life that much. Shows how strongly the principles are held, imo.

'loftily proclaim one's utter disdain' -there's usually nothing 'lofty' about the aftermath of an affair: they ruin lives. Emotions are raw and gritty, including those of family members, relatives and friends who often find that they too have been lied to, and find themselves supporting betrayed partners going through what is often the worst time of their lives.

If OP's family only blamed, punished and blanked the OW, then that would be misogynistic. But the OP makes it clear that nobody is condoning the male affair partner's behaviour either -the thread isn't about him, they are clearly making their feelings known and are meting out family 'justice' on him too (which he, like an entitled bloke, appears to be resisting).

Phrases like the one quoted makes out that family members who feel hurt by an OW's participation in the break-up of their immediate or extended family are somehow unreasonable, irrational, inconsistent, unprincipled and woman-hating. Giving affair partners some kind of 'free pass' because they didn't make the vows entirely robs said affair partner of agency. They did a shitty thing. They behaved like a dick. They intentionally caused harm. They could have chosen not to, but they said 'Yes, I deserve this person's spouse'. It is definitely OK to express disapproval and hold affair partners -male and female- to account. And it's never usually either / or. We're stuck with our cheating family members: they remain our sister, our DC's dad, our BiL or our aunt, however much we seek to distance ourselves from the damage they caused. Whether we like it or not, however hurt by, or angry with or bitterly disappointed we are in them, they remain in our family system, regular reminders of betrayal and deceit. It sucks. Few families close ranks around cheaters -rather, their actions cause rifts and fall-outs which last years if not lifetimes.

I so wish MN would quit it with the 'no shade on the OW'. The argument always feels rather academic and far removed from the coalface of messy, overwhelming emotion in the aftermath of an affair -it shames betrayed partners and their families at a time when that really is the last thing they need.

His poor treatment of his wife would mean that no, I don't want to have anything further to do with a clearly nasty, lying, prick.
Not a chance.
No one would be telling me as an adult, whom I have to be around either.

I’m with you there @Sxwer

I am in a similar situation op. My sibling, cousins and I have do not engage with my uncle's partner who he had an affair with for many years unknown to my Aunt.

I have met her once at a funeral but just made small talk about the weather and parking. She is not invited to any family gathering nor do we attend events that they host. If I am honest I have little to do with my Uncle either.

I think if you are still willing to have a relationship with your uncle, he comes as a package with his partner and you need to accept that.

Presume your aunt isn't a blood relative so over time she will probably distance herself from you as her life moves on.

Personally I wouldn't want to be best buddies with the other woman but, if they stay together forever, they will both be part of your family for a long time.

Quite - hypocritical.

No, I would disagree with this. They are both jointly responsible, both to blame. Both scum. Both can’t keep their genitalia to themselves. It’s not just about who was the married one, she knew and she went ahead anyway. No worse but also no better than OPs uncle. Fault lies jointly with them both.

Oh FGS you have absolutely no idea what the uncle told the AP. Probably the usual hogwash about them being separated but still living in the house or nonsense about DAunt being disconnected for years. For all we know he could have lied through his teeth or not of course but the fault is with the man here or are women always responsible for what men do??

I don’t really go with the mumsnet view of punishing people; for me a marriage always has two sides to the story and contrary to popular belief 0n here people seldom leave a happy loving marriage. So I’d assume the marriage wasn’t working. Otherwise sure he may have cheated but he’d not have left

so I don’t judge, and would simply continue to see them all.

Doesn't matter what the uncle told her. He was MARRIED and she should have said not now.When you're DIVORCED come and chat to me then.

This is ridiculous, you have no idea of the state of rhe marriage, the happiness of compatibility levels, why the affair happened, why he chose to leave his marriage or what it was the affair partner knew. Very few women shag a man who says I love my wife dearly.

Its nothing to do with your family friends who you spend time with. You dont have to see them just because your uncle is family !

My uncle is married to someone who many of us refuse to have anything to do with. She treated my late grandparents terribly and is a lying cow amongst other things. Yet my uncle as chosen to stay married to her and brings her to family events. We ignore her, if she was to attempt to talk to me I dont know if i could keep my mouth shut.

I disagree. The state of the marriage ahs nothing to do with it. If the marriage has broken down then you end the marriage. Then you go shagging around with whoever you like. No one is being deceived!!. It's simply about doing the right thing and being kind to other humans I.e. The uncles then Wifw. Morals are for a reason. These kind of humans are despicable and should be shunned. I wouldn't want that kind of person in my life and glad to say I don't.

Sure, no one is disputing he should not have had an exit affair, but he did, it doesn’t change the fact that’s exactly what it was and if the marriage was happy he wouldn’t have done it.

no one leaves a marrage that is happy and loving. No one, sure some cheat for thr excitement etc, but they don’t leave proactively. So the marriage was failing. I’m not disputing he should have ended it first, but it’s quite common tk look for a soft landing before exiting a marriage that’s unhappy

I would move on -" let he who is without sin".

And that's where humanity falls down. All those women and children and men in some csse's left devastated because of NOT DOING the right thing. Dishonest, disloyal, low morals, cheating, deceiving, no dignity, no integrity, two face, lying, scheming, coniving types. Who in their right mind would have such people in their lives. Forgive, forget and move on. Bur don't give them the time of day.

I think he is much more, possibly entirely, to blame. We don't know what he told his affair. Many men tell women that their marriage is over, that they are only cohabiting because of financial reasons/ the kids/ you name it. They go on holiday with the women, go out in public with them and can be called any time. It can be surprisingly difficult for women to figure out that they are involved in an affair. Men usually don't tell women that they love their wives and just want a bit of nooky at the side.