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Original poster

Should I tell his fiance he cheated

168 replies

Hopelessnaive · 28/03/2025 16:23

I met a guy at work a little over 18 months ago. We became friends straight away, within 2 months it turned to more than friendship. We talked all day everyday, spent every minute we could with each other. I really fell for him. He always said he wasn't looking for anything serious at the moment and didn't want anyone at work to find out as it would make things awkward for both of us. I never pushed him, but I hoped that one day he would change his mind. I knew he was the one I wanted to be with.

Only it turns out I was a complete idiot. Not only does he have a long term girlfriend (around 10 year relationship) but they've also recently got engaged. No wonder he wasn't looking for anything serious.

I am absolutely devastated. Ive barely stopped crying since I found out. He's now ghosting me as he knows I know. Im not even worthy of an apology or an explanation. I obviously never meant anything to him.

He doesn't use any kind of social media, or I'm sure I'd have found out sooner. But I've found out who his fiance is through other colleagues, and after a little searching I've found her on Instagram, so I could send her a message. I just don't know what to do. Do I send her a message and tell her he's been cheating on her for over a year, or do I just let it go and say nothing and try to forget him?
Part of me is angry and wants to spoil his relationship to hurt him. Part of me thinks she deserves to know, especially before marrying him, and part of me thinks I'd just get turned into the bad guy and maybe she'd forgive him.

YABU- don't message her.
YANBU- message her and tell her everything

OP posts:
MesmerisingMuon · 28/03/2025 17:48

I'd tell her. Think carefully about what you say so you don't come across as a vindictive psycho!

I'd message her something along the lines of "hello. Apologies for the strange message but I've just found out my boyfriend (Twats name) of 18 months has a fiancée. After asking some questions your name was mentioned. I'd like to apologise if this information is correct. I had no idea he was seeing someone else, let alone engaged, so this has come as quite a shock. If I'd have known, I would never have got into a relationship with him. Needless to say we broke up once I found this out, and do not want to hear from the deceitful twat ever again. "

EmeraldShamrock000 · 28/03/2025 17:55

Yes, he deserves to be found out.

Are you sure you didn't know that he was in a relationship. Seems unlikely when your colleagues knew.

incandescentglow · 28/03/2025 17:56

do ittttttt don't let him get away with it
you may get a bit of backlash but she might equally be grateful and thank you for stopping her wasting any more of her time
definitely have as much proof as possible in case they gang up and fight back BUT there is a chance she has had an inkling or gut feeling and this will be what settles it
good luck and take your time to heal, everything will be okay x

Offtobuttonmoontovisitmrspoon · 28/03/2025 18:00

I think it depends.

If it was sexual then absolutely tell her so she can decide whether to marry him.

You need proof because without it why would she believe you.

I don’t think that you should do it though, it’s unlikely that she will believe that you didn’t know. Can someone do it on your behalf?

largeprintagathachristie · 28/03/2025 18:02

The op wrote they became “more than friends” so I assume that means a physical relationship.

Some posters are asking.

Op, do clarify if I’m wrong, as it will influence the answers you get.

BubbaHorovitz · 28/03/2025 18:02

Is he your superior at work or an equal? Because HR and "gross misconduct" comes to mind.

LentLily25 · 28/03/2025 18:08

largeprintagathachristie · 28/03/2025 18:02

The op wrote they became “more than friends” so I assume that means a physical relationship.

Some posters are asking.

Op, do clarify if I’m wrong, as it will influence the answers you get.

I agree - if it was an emotional relationship rather than a physical relationship it makes a difference.

jacktheladess · 28/03/2025 18:08

A bit outing, but when I was in this situation instead of telling HER I told HIM I had an STD. And I really suggested he got tested. Getting tested for a man (in those days) was a very unpleasant experience. Don’t feel guilty at all.

Jackreacherstrousers · 28/03/2025 18:10

Don't tell her, you will only end up the bad guy (or woman in this case) she probably won't
leave him or even believe you!

Realistically what do you want to gain by telling her? Do you want him back? or are you just wanting to cause hurt because you've been dumped?

CreationNat1on · 28/03/2025 18:15

Tell her, factually.

Hello, I met x in month year, within 2 months we started dating. I recently found out he is in fact engaged and I am no longer in romantic contact for that reason. I thought it best to tell you, so you have full knowledge of x s character.

Pandolly · 28/03/2025 18:20

I'd want to know if I was her, but I'd probably be suspicious unless I saw evidence to prove what I was being told.
I hope you're doing OK, what a shitty thing for him to do to you and her.

ThreeLocusts · 28/03/2025 18:22

Sorry about the betrayal OP. I'd tell her, along the lines of messages already suggested up thread, offering to provide evidence if desired. His fiancee deserves to know. Since you don't know her personally, hopefully the fallout for you will be limited.

LentLily25 · 28/03/2025 18:28

I wouldn’t want to tell her to hurt him, but to prevent her from being hurt. In her situation, I’d want to know. Also, raise your bar.

Marble10 · 28/03/2025 18:31

I think it depends on the extent of your ‘relationship’ , you haven’t exactly said if it was physical or if it was just emotional (yes it still hurt but it does make a difference). Ie. If it was just emotional, it could be turned on you that you are a crazy work friend who has a crush. Whereas if it’s been physical and you can prove it then it will look as it was him too. I’m assuming he was casual, but you fell hard. So that would then go to the reasons you want to tell her. You seem to want to get back at him for revenge rather than genuinely caring for her knowing and her relationship. If it’s just for revenge, it’s not going to make you feel better and it’s not going to bring him back to you.

Sassybooklover · 28/03/2025 18:59

I think you need to to be sure if you decide to tell this man's partner, simply because you work together. What will the fallout be for you at work, if he finds out (and he will), that you told his partner? Is he a more senior than you or are you on an equal footing? Is he likely to cause issues with you at work with colleagues? Do you have to work with him on any level? It's easy to say, his partner deserves to know, and yes she does but not to the detriment of you!! If there could be a nasty fallout at work, then you would be better to chalk it up to experience, block him and have as little to do with him as possible. You also need proof, no point in telling her without any evidence to show. He'll just make you out to be some crazy loon who fancies him and is a stalker. Without evidence, there's no point in telling his partner, it would be his word against yours, and she'll believe him, not you. I understand you are angry but you also need to be telling her for the right reasons, rather than trying to seek revenge on him!

BubbaHorovitz · 28/03/2025 21:32

No don't tell her. She might go mental on you.

singlewhitetrashheap · 28/03/2025 21:33

Of course you tell her!

SmugglersHaunt · 28/03/2025 21:37

I don’t believe your account at all. Leave it and move on

Bridezillasista · 28/03/2025 21:40

This reply has been withdrawn

The OP has been identified in real life, so we've agreed to take this down.

meganorks · 28/03/2025 21:49

Honestly, no, I wouldn't.

What do you stand to gain? I can't see any way where this benefits you, but there is potential to make things worse.

Best case: she appreciates you contacting her, breaks of the relationship, he sculks of somewhere to another job and you get the satisfaction of knowing he fucked you around but he got his comeuppance.

But what are the chances of that?! Much more likely are any number of scenarios where a lot of unnecessary drama comes back at you. Especially since you work together!

Forget about him. Move on and thank your lucky stars it's not you marrying him

ByTicklishLimeBalonz · 28/03/2025 21:51

this is why i have copies of all texts and watsapp etc

Fancycheese · 28/03/2025 21:52

Nope. Don’t. I think this backfire really badly on to you. I understand the desire to tell her, bur honesty I’d focus on yourself. Start by looking for a new job and take this as lesson not to get involved with people at work!

arcticpandas · 28/03/2025 21:54

Do tell her. She deserves to know before marrying the prick. I imagine you have text messages to back this up?

BlondeMummyto1 · 28/03/2025 21:56

No. It will make work difficult for you if she’s friendly with colleagues.

SmurfKingdom · 28/03/2025 21:56

Can’t believe how many people say not to tell. The partner deserves to know her fiance is a cheating prick.

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