...to not be upset after leaving after 28 years together?

Good for you !

You may think / believe you have forgiven, but clearly you have not ' forgotten '.
thus you could not move on from that.

Invite the children round to visit / have dinner.

Do you plan on them living with you during and after the divorce ?

Will the family home be sold for your 50% or can / will he buy you out ?

She is allowed to use money for these reasons, but it doesn't mean that it wouldn't be taken into consideration during a divorce.

Simply, as far as the info we have, she has taken this windfall ( for all we know is 5k) and unexpectedly started the process of divorce; she's not under any threat, there's been no conflict, etc, she has decided to move out and potentially used joint money to do that. It's not as black and white as you're trying to state by just saying ' you're wrong' when I'm not; I'm merely pointing out what could happen.

I smell a reverse. No-one describes their own drastic actions like this as 'a whim' or dismisses their kids like this.

Come on, 'fess up, OP.

What are you planning on doing after the 3 months ? Do you have the means to carry on paying the rent, if so fair enough.

The fact you havent told the kids where you are would suggest that maybe after the 3 months you are planning to go back to the family home, and what you are doing now is a punishment to him rather than you leaving.

I don't blame you OP. And whatever he admitted to, was probably worse. It generally is, as we see on here often.

It all seems a bit odd to me. There must have been other stuff in the relationship you weren't happy with. i've been married to my DH for nearly 30 years and I'd be pretty pissed off if I found out he'd had an affair in the early days but I can't imagine walking away at this stage of our lives.

If it was now or recent I would but not 22 years ago! Were you honestly that happy before this revelation?

I also have adult DCs who have moved out and I would tell them, don't leave them in the dark about this as it does affect them hugely. Mine would be very upset.

The OP has left the marital home and is renting because she has not been able to come to terms with a betrayal which was hidden for 22 years.
I hardly think she is going to be the one who is financially better off, especially if she has also the one who has spent much of those 22 years raising children.

yet you replied?

I doubt it's a significant sum of money as the op states it was a 'modest windfall' which suggests maybe a few thousand not hundreds of thousands of £s otherwise I'd imagine she'd buy a flat rather than rent one

The courts may be interested in how much she had and what it was spent on, but if it was a few grand and spent on housing herself, they are not going to consider that as hiding assets in a divorce.
I don't know if she's hiding any money, but as she hasn't mentioned it, I'm going to assume she hasn't. Why do you think she is hiding money?

I would agree with this.
You are an adult and you do not have to disclose your whereabouts to anybody. But it is important to let the DC know you are okay and it is not anything they have done.

5 years isn't a whim, really.

But like PPs have said, please tell your children you’re okay and not to worry.

You do need to let your child know though

YANBU to leave, or to feel how you feel, YABU not to tell your kids where you are and talk to them about it. Even if they are adults they will still have feelings about their parents separating.

I’m not surprised your kids think there’s something wrong with you. Why punish your kids by refusing to tell them where you are? That’s cruel.

It does seem an extreme reaction to a couple of ONSs a lifetime ago. But any long marriage will contain a lot of compromises and restrictions as well as the good stuff, and maybe you just don’t see why you should do that any more. Hope you are ok.

Well done!

The thing is, by not telling you about the “fling” at the time, he manipulated you into having that relationship for so many years that you may or may not have chosen had you known.

By telling you when he did, I bet he felt lovely and free and as though a weigh had been lifted. But what he essentially did was pass that weight on to you.

Having had the fling and decided not to tell you at the time, he should have taken the secret to his grave, however much it weighed on him. It was his burden to carry.

Of course you can’t view him the same way now you know. He’s not the person you thought he was.

That all said, I wonder if there were other issues that were causing you to resent the relationship slowly over the years?

Nothing to stop you leaving your husband if you feel your marriage is over, but the not telling the children is worrying to me. Not only will it be very stressful to them, but it does kind of suggest you might not be in such a good place mentally as you say? Why has it been so difficult to tell them where you are? Do you think you may be feeling a bit numb and in shock. Look after yourself.

He kind of lost the right to have a talk it through conversation when he decided sticking his dick else were was the answer rather than a conversation all Those years ago.

You're wrong 🤷‍♀️. She hasn't said anything about hiding money. She's allowed to use money to pay for her accomodation, the same as when the man moves out of the family home.

I find this quite psychopathic tbh. Your poor kids. Adults or not you've completely upset the whole course of their future lives on a whim. You've let self righteous anger overwhelm you rather than doing the responsible thing and talking it through with your husband.

But 'you go girl' and all that shit I guess.

I’d let your children know where you are.

But him? Nah he betrayed you then years later confessed to ease his conscience he must of been over the moon when you seemed to forgive so easily.

You’ve tried for 5 years to work though it but you can’t so you’ve left. That’s fair.

Enjoy your new home.

Our two kids are old enough to be independent, they know I’ve left but I haven’t told them why or where I am for the time being.

If my mother had just upped sticks without warning and refused to tell me where she was, I'd be very, very worried too. Probably would have thought she was having some kind of breakdown.

I know you said you had no difficulty in saying you forgave him after the big reveal, but you clearly didn't (fine). Equally, you say you still love him very much but it's clear that you don't (also fine). People who love their partners very much generally don't pull the plug so bloodlessly and finally, without any prior warning. I do wonder whether you stuck around with him because it was comfortable until something better came along (the windfall).

how do you know she's not hiding the money?

It also depends on what type of windfall it was, to me a 'windfall' suggests a win, perhaps the lottery, this, espically given the length of the marriage, would be considered a marital asset.

I think the courts would be very interested.