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Relationships

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Husband suggested opening marriage and mentioned my sister, am I overreacting?

341 replies

Falalalalalala86 · 16/03/2026 18:38

Posting in relationships for more traffic as haven’t been able to stop thinking about this. It feels quite petty compared to some things on here but it’s been playing on my mind all day.

DH and I have been together 12 years, married 7. Two kids (9 and 6). Generally we get on well.

Last night after the kids went to bed he asked if we could talk. I assumed it was something normal (finances, holiday plans etc).

Instead he asked if I’d ever thought about “opening up the marriage”.

I genuinely thought he was joking at first but he was completely serious. He said lots of couples do it now and it can actually make relationships stronger.

I was really taken aback and said absolutely not. He then backtracked a bit and said he was “just curious” and we don’t have to do anything.

But it’s really unsettled me.

I asked where this had come from and he said it was just something he’d been reading about online.

Here’s the bit that’s bothering me though.

When I pushed a bit more he eventually admitted there’s a specific person he was thinking about.

And it’s someone I know.

It’s actually my younger sister.

Apparently she’d joked with him a few weeks ago about “modern relationships” when we were all having drinks and he says that’s what made him start thinking about it.

I feel completely weird about the whole thing now and honestly a bit sick.

He’s saying it was just a hypothetical conversation and I’m massively overreacting.

But I can’t get past the fact that he clearly has been thinking about my sister in that way.

AIBU to think this is completely inappropriate or am I turning something stupid into a huge issue?

OP posts:
NoYourNameChanged · 16/03/2026 19:17

Petty?! This is many, MANY things but petty is not one of them. Marriage ending though, yes it’s that.

JustCoralGoose · 16/03/2026 19:17

I would file for divorce

Kissmystarfish · 16/03/2026 19:17

Falalalalalala86 · 16/03/2026 18:38

Posting in relationships for more traffic as haven’t been able to stop thinking about this. It feels quite petty compared to some things on here but it’s been playing on my mind all day.

DH and I have been together 12 years, married 7. Two kids (9 and 6). Generally we get on well.

Last night after the kids went to bed he asked if we could talk. I assumed it was something normal (finances, holiday plans etc).

Instead he asked if I’d ever thought about “opening up the marriage”.

I genuinely thought he was joking at first but he was completely serious. He said lots of couples do it now and it can actually make relationships stronger.

I was really taken aback and said absolutely not. He then backtracked a bit and said he was “just curious” and we don’t have to do anything.

But it’s really unsettled me.

I asked where this had come from and he said it was just something he’d been reading about online.

Here’s the bit that’s bothering me though.

When I pushed a bit more he eventually admitted there’s a specific person he was thinking about.

And it’s someone I know.

It’s actually my younger sister.

Apparently she’d joked with him a few weeks ago about “modern relationships” when we were all having drinks and he says that’s what made him start thinking about it.

I feel completely weird about the whole thing now and honestly a bit sick.

He’s saying it was just a hypothetical conversation and I’m massively overreacting.

But I can’t get past the fact that he clearly has been thinking about my sister in that way.

AIBU to think this is completely inappropriate or am I turning something stupid into a huge issue?

Yeah. I’d be gone

no way would I be ok with the sister thing. The open relationship wouldn’t bother me one bit

but the sister. Nah. He’s be gone before the door could hit him

mathanxiety · 16/03/2026 19:19

Hopefully you've now told him to pack his stuff and find a bedsit to live in?

This would be the end of the road for me.

Sunshinemoonlightboogie · 16/03/2026 19:20

That would mean the end of my marriage. I would be utterly disgusted by him.

NovemberMorn · 16/03/2026 19:20

It's a huge issue and he's a twat for even thinking, never mind talking about it.

wherearethesnacks · 16/03/2026 19:20

It's almost impossible to believe any man could be stupid enough to suggest that.

I assume that today you've been gathering together all the infomation you'll need on your joint financials.

MrsElijahMikaelson1 · 16/03/2026 19:21

Fuck no. Ask him to leave. I would never be able to have sex with that man again.

MsSmartShoes · 16/03/2026 19:22

I would suspect that he and your sister are further along on this…

icreatedascene · 16/03/2026 19:23

I'd be concerned that there isn't something already going on between them. It just seems such a bold suggestion, even if you are into the sharing scene. He's basically told you that he's been thinking about shagging your sister and wants your approval. The cynic in me thinks they could already be at it and he's trying to legitimise under the open marriage guise.

Tablesandchairs23 · 16/03/2026 19:23

He wants to shag your sister. Where do you go after that!

NewZebra · 16/03/2026 19:23

WTF. That’s unforgivable.

Lostworlds · 16/03/2026 19:24

Pretty hard to forget and move past if i’m honest. I know people have thoughts but he’s wanting to act on his and they are with your sister which is massively upsetting.

To me, it sounds like him and your sister had a bit of a flirty conversation recently and I would want to know more about what was discussed and if they have carried on chatting. Seems like an odd thing for him to suggest if he wasn’t sure your sister was interested.

icreatedascene · 16/03/2026 19:25

Tablesandchairs23 · 16/03/2026 19:23

He wants to shag your sister. Where do you go after that!

Exactly! And even in the parallel universe that a woman would be ok with that, how do you go about that? Is the OP supposed to suggest it to her?

Pebbles16 · 16/03/2026 19:25

Absoutely unacceptable. I am so sorry @Falalalalalala86

TomatoSandwiches · 16/03/2026 19:25

So you had this conversation and then happily fell asleep next to the fucker?

Why did you not make an appointment with a decent divorce solicitor the next day?

Sassylovesbooks · 16/03/2026 19:26

Your younger sister mentioned about 'modern relationships' in a joking manner to your husband. I'm not even sure what 'modern relationships' statement is meant to be! What did she actually say to him, did he tell you? From this conversation, I have to assume he thinks your sister is lusting after him, so he decided to throw in the 'opening up the marriage' line, to test the waters.

If you agreed to 'opening up your marriage', it would mean he could legitimately shag your sister, without 'cheating' and no guilt. In turn that would mean he could shag other women too.

Your husband has realised he's fucked up big time. Not only did he mention 'opening up the marriage' but he told you he wants to shag your sister. Of course, he thinks you're overreacting, he now wants to forget the entire conversation and pretend it didn't happen.

You can't forget it though. For me, it would be bad enough he is suggesting 'opening up the marriage'. I understand couples swing, I'm no prude and if it's something both want, then I'm not judging. It's the sister element, that is just awful, that is inappropriate and it's yuk. I'm not sure I could forgive.

icreatedascene · 16/03/2026 19:26

Tell him it's a great idea because you've been wanting his brother for years.

Farkinhell · 16/03/2026 19:26

If there was a vote I reckon it's be 100% in favour of you dumping this arsehole and moving on in life without him.

Shitmonger · 16/03/2026 19:27

I would end the marriage over this.

Your sister probably made an innocuous comment referring to both parents working or some such and the delusional man has taken it as some sort of hint that she “wants him.” Yuck. He’s like those men that think that a shop assistant smiling at him means that she wants to sleep with him. 🤢

FryingPam · 16/03/2026 19:27

Hoping this isn’t serious, but if it is:
Asking you whether you’d consider opening up the marriage and accepting a no: mmhhmm…okay.
Thinking of having sex with your sister: divorce lawyer now.

Catcatcatcatcat · 16/03/2026 19:27

TheSpottedZebra · 16/03/2026 18:39

A huge issue for me. As in, probably marriage-ending.

Yup. Me too.

ilikemethewayiam · 16/03/2026 19:27

The fact that he’s even entertaining these thoughts means that you and the marriage are not enough for him. He wants sexual excitement with someone new (whether it be your sister or not). He wants an affair but with the luxury of an agreeable wife so he can have it all without the disruption of a divorce. He clearly couldn’t care less that someone else would be having sex with you or that you could potentially fall in love with them and consequently leave him.

It would be the end for me OP. I couldn’t get past that.

Ritasueandbobtoo9 · 16/03/2026 19:27

Disgusting. What a prick.

Thisismynewname23 · 16/03/2026 19:28

This is terrible, I am so sorry for you, what is your relationship like with your sister? Has he mis interpreted or has she likely
raised this? It would finish both relationships for me x

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