AIBU to think dB must have known they were cheating?

[Kertrats]

My dB has discovered his wife has been having an affair with his best friend.

Background: he and his best friend met his now wife when she started going to the club where they both drank.

My brother and her have a fling but he ends it as he does not want to have a relationship with her.
She then starts having an affair with his married best friend (who at that point has small children). This apparently ends.
My brother, who is a nice guy but quite lazy, moves in with her. My parents want him to move out and they become a couple.
She accidentally gets pregnant.

When the child's a toddler, he regularly- as in every Monday evening-takes their son to our parents. When he's at our parents his best friend calls around their house to spend time alone with his wife. This is a regular thing.

(This is no secret, dB was fully aware he did this.)

Now he discovers they've been cheating again.
He appears distraught but I can't help but think he must have known.
I ask because his laziness has made him quite manipulative and I'm a bit dubious about this 'woe is me' reaction.
She was a strong capable single mum when they met and he long-term out of work.

I don't intend to 'do' anything different with the replies (if any) I get here. I will show sympathy regardless but AIBU to be a bit cynical here?
I mean he must have thought something was off, right?

Definitely. Bizarre! What on earth did he think they were doing!

Does it matter?

I had no idea my ex was cheating when he had to "work late" which meant being "put up in a hotel" over night. 🤷🏻‍♀️

Well, you’d think so. But if you are happy in the relationship and are told all is well, you be,ieve it for fear of rocking the boat.

I knew somethign was wrong when my ex was having an affair. I just knew something was off. But logic told me all was well - we still slept together, he came home on time, we talked about the future….but my heart knew.

You need to be supportive, not accusatory. He is upset. He has been betrayed. Just support him.

It doesn't sound as though he loves her, it's been easy and convenient, so being distraught seems an over reaction. It's as though he's got out of the way to give them the opportunity. Has he always been so passive?

It sounds to me like he's a victim of much wider abuse than just the cheating, in my opinion. Someone who is so indoctrinated that they don't see something this obvious is far more likely to be a victim of gaslighting and coercive control (if not even more than that) than just wildly stupid. He probably felt completely trapped too - she was a strong, independent, single mother who didn't need him. The best case scenario for him if he left this abusive relationship would be having his child 50% of the time, many people will allow themselves to be abused or manipulated or blindfolded in order to see their child every day.

I’d have questions as to paternity tbh.

Thanks for replies. I appreciate that some people have sadly been cheated on in past (myself included) and yes you don't want to believe it but these set of circumstances is somehow so obvious that it seems unbelievable he didn't know.
He may have been abused but I also think he used her. No relationship wanted until he needed a place to live.

My concern is that he'll play this as a card to move back home or to deflect from his own shortcomings.
My parents don't really need an adult son of 40 living back home.

#Ponoka7 'fraid so. Long - term of work and to be honest if my parents hadn't put pressure on him to leave when he reached his early 30s he'd still be there today.

Yep. That had crossed my mind, too. I don't think this affair ever really ended. Maybe on hiatus when she was pregnant just given birth.

Eurgh! Sounds like your DB and his friends are really enmeshed and enjoy lots of drama.

I am guessing that you have switched off from his needs and are more bothered by the possibility that your parents will be used and abused by him and that's really difficult to do as they will probably be happy / well guilted into helping him.

Families! Who'd have 'em?

The whole best friend-wife-my dB arrangement is really weird.
I can't help but think he gave tacit permission by leaving them alone together.
I believe he used her as a replacement mother as he is honestly useless at life.
He moved out to live with an older woman, they split, he simply couldn't cope and moved back in with my (our) parents.

I do care for my dB but I honestly think he did/doesn't give a fig that his wife cheated really and is over-egging the distress for sympathy points.

Maybe move back in with mom and dad for a while. 🙄
And that's what bothers me.

Sounds a bit messy. I'd leave your parents to decide if he should move in with them. Or maybe he could move in with you.