My sister is having an affair, im the only one who knows

[Crimble123]

She's put me in an awful position and im so angry at her.
She has 2 small children and a long term boyfriend. Given the boyfriend is not perfect and he hasn't always been there for her but he is a good dad and works hard. He gives her all the money she could want and she doesnt work.
She herself doesnt treat her boyfriend well either.
This new guy she met off the Internet is way older than us. She hasn't known him long and already there is drama better them both apparently. She told me last week he blocked her because she started on them. She's making excuses all the time to not be at home and meeting this guy. Her boyfriend is with the children and taking them out alone. I feel so sorry for them but I cant say anything.
Ive text her and told her to sort it out. Either leave boyfriend or cut it off witg the other guy. She wont though because she gets all the money she wants, if she left she would have nothing.
Its becoming more obvious as shes acting so suspicious. Our mum is suspicious. Last week me and her were out and she wanted to leave early she said because she weren't feeling great but I think it was so she could see this other man.

What do I do? Im feeling more and more angry at her. I just feel shes going to ruin christmas some how because thats the type of person she is. I don't know what to do

Stand back and wait for it all to go tits up. Which it will, and there is nothing you can do about it.

Keep out of it. Let her give herself away, distance yourself from her and tell her her you don't want to hear any more details of her affair as you don't approve. You don't need to be part of it!

Say nothing and don't get involved. Do not have a paper trail with your sister regarding this. When it comes out ( which it will) she will look for somebody to blame or to be an accomplice and it will be you.

Distance yourself and don't engage with her at all regarding the affair.

This already sounds very messy. All you can do is distance yourself.

Ive had the worst afternoon. I popped in to see my parents and her boyfriend and my niece/nephew were there. Apparently she was on a "spa day". I know full well she isnt, she hasn't told me she is with him but its obvious.
Her boyfriend looked a broken man and was asking me questions around her recent behaviour and do I know what's up with her! I had to lie obviously and I feel awful.
Then when he left my parents were talking about how her behaviour had changed in the last 3 months and they were trying to work out what was going on. Im sitting there knowing why and it was horrible.
Its all a car crash waiting to happen.

I just feel for the kids so much! She doesnt want to spend any time with them. Any chance she gets shes off here and there telling her boyfriend shes seeing mates when shes not.

I don't think you'll have long to wait, this is going to erupt very soon Id say. It already is. I'd just wait it out and let them have their say, saying nothing. I'd then try to avoid your sister so you don't get dragged into anything new. He will find out soon and then it will all be over. I'm really sorry you are going through this through no fault of your own.

You don't have to lie, you're choosing to.

I wouldn't be lieing for my brother in this situation. I'd be saying "That's not where he is" and then when the partner wanted more information I'd tell them they needed to speak to my brother.

Yeah, it's probably ruin my relationship with my brother, but that's on him, not me.

It's not an affair if she's not married - but she is cheating and that's not fair on her boyfriend.

Keep out of it. She’s not married to either of them. 🤷‍♀️

Back off and let her enjoy some time with this new guy. You don’t know how bad it is for her behind closed doors with her husband, this could be the only thing she has going for her at the moment so be a good sister and try to support her alright?

Well you’ve got two choices really, keep quiet and when she gets found out hope she doesn’t tell everyone you knew all along, because you’ll be blamed too. Or tell your parents and her boyfriend and you’ll still be in lumber for bit saying anything sooner.
Personally for the children’s sake if nothing else I’d tell.

@Swiftasthewind what a total joke of a response

only on mumsnet !

Yep. Probably a cheater herself and that’s how she justifies it. Theres no excuse in my book for lying at cheating. Sure people fall out of love and in love with others while in relationships. But you end one before you move onto another.

You are in an impossible position.
Unless he is totally thick he will work it out and probably has already.
If he asks again re her behaviour just ask him what he thinks. If he says no clue, say so why should I know, You must have some ideas as to why she is always out.

he needs to be encouraged to think the unthinkable and do his own digging

It's cheating, and she is massively using the boyfriend.

😱😱

I'd just be telling him he should ask her.

I know my sister. She is no saint. She has been physically violent to her boyfriend in the past. So many other things. He may not always be there emotionally for her as he struggles with that stuff but she isnt an angel herself.
She is using him for his money atm whilst leaving her children to go and cheat regularly.

When shes angry she goes crazy so I would not put it past her to drag me down too. I hate her for putting me in this position.

I would tell your sister that you won’t continue to lie for her. It sounds as if her boyfriend knows she’s cheating. It’s going to get very messy.

@Sunshineandgrapefruit , Affair - Wikipedia

An affair is a relationship typically between two people, one or both of whom are either married or in a long-term monogamous or emotionally-exclusive relationship with someone else. The affair can be solely sexual, solely physical, solely emotional, or a combination of these.

Of course it’s an affair! You don’t have to be married to have an affair. She has a long term partner with kids 🙄🙄🙄

You are a moral agent and you have choices. One would be to say, "I'm not going to cover for you any longer. I'm sick of having to lie for you. You can tell your partner the truth or I will. I'll give you a week to come clean."

Then the type of person she is will go gunning for op when her world implodes

I think you should tell your sister that your patents are getting suspicious and that if your mum asks you outright, you're not going to be able to cover for her. Ot would make things less stressful for you can get her to tell your mum, gives you someone to share concerns with.

And you can tell her that he's noticed something is very off, and remind her of what she'll lose when she's found out.

The easiest way is to answer a question with a question
when they start going on about your sister
ask them what do they think she’s up to

asking which spa gas she gone to ,who with thing like that

one thing u will have to do is come clean immediately when this blows up as she will throw u straight under the bus

her boyfriend deep down probably already knows
but considering he puts up with her hitting him using him for money no doubt when they split she’ll weaponise kids and make his life he’ll be in denial