Am I wrong?

Not unreasonable at all - could you maybe suggest to DS that instead of having both weekends per month at your house he only does one? That way you still see your extended family, but it’s not quite as disruptive to your own routine?

Sincerely hope you don’t cook etc for them all!

No of course you're not!
As usual the best course of action is talking it through with your son.
It may take a lot of patience on your part, because he obviously isnt thinking clearly or he could have worked out for himself how difficult this is for you.
Best of luck

@Lolo81 that sounds like a plan. I hope this reply reaches you as I am new to this!

It looks like he's abdicating child care to you and that's not on! Maybe once a month or he brings them each time for a couple of hours but you will have to talk to him and tell him it isn't suiting you.

You are not being unreasonable at all.
One of our daughters moved home just before the first lockdown with three children.
We do have enough space, but all three adults in the house work full time. When I get in I get supper, then normally one of them has a activity, so I’m babysitting.
I love them very much, and I’m relieved that they’re out of a bad situation, but I’ve raised three children, and I don’t want to start again.
I so miss my quiet evenings, and my tidy home, it’s quite hard at times.
The one respite is when two of them go to their dads on Saturdays, so I completely know how you feel, but you probably feel as I do, that the children have to come first,
It’s a difficult situation.

Does your son have his own home?
How about suggesting he has all three children there, and you visit him, for part of the weekend.
He may, of course, think he is doing you a huge favour letting you share a weekend with his children. Seriously.

Why do parents assume that because we love our grandchildren, we should be thrilled to spend every minute with them?

The weekends are for his access, so there is nothing to stop you going out for part of the days, having lunch with a friend, visiting the library, seeing a film, these will all be available soon. Three children for 48 hours is exhausting, and you need to have a firm but friendly chat with your son about how it makes you feel. Ask him to come up with solutions?

Of course not!

You are entitled to your own time, but you also want to see your grandchildren, or I assume so.
When they visit do they muck in? Respect your rules? Do you make them feel too welcome?
Why not meet up with them outdoors, so you can get your South Downs and they won't be messing up your house?
Do they live too far away to come for just one day?
Why not go to them sometimes and have them wait on you?
I have a family member who years ago would turn up every Saturday afternoon and never leave. We didn't invite them and at first it was nice to see them, but it went on so long we began to resent it.
We decided to go out ourselves on Saturday afternoon and eventually they went to visit my mum instead!Some people are just like that.
I would choose an option that shows them you have your own life and, as far as possible, see them on your own terms.

You don't mention whether your son is also with you for the 48 hours. Presumably they all stay over and you are cooking for them for two days. I think this is too much. Your son is using you as a substitute mother during that time, expecting you to be the other adult carer for his children. I understand it can be difficult for single parents when it's their turn for childcare, but this is the bed they made. You need to decide what you are prepared to do and then have a talk to him, explaining that 48 hours is too much for you. Hopefully you can come to an amicable agreement.

I would tell your son that your work load has doubled and you need more time for work at home. Tell him you need the visits to be cut down for two days or miss out a weekend. As you feel under pressure and it would help when they are there if he could help out with food prep etc.

What is wrong with men who are unable to parent their own children in their custody time?

He needs to grow up and face his responsibilities.

Redhead56 has good advice.

@Paillasson - you’ve got the hang of it no bother! Hope everything works out well for you.

There are two fathers in our situation, and they are both a complete waste of space, neither pays a penny toward their children, and one hasn’t seen his child for a year.
Neither are silly young men who don’t know any better, both in their forties, they don’t have an ounce of pride between them.

YHBVVVU to put up with this for 3 years without sorting it out. However good luck with implementing suggested changes - hope you’re not seen as being selfish.

I would do as others have suggested and cut it down, maybe just one day every two weeks. I don’t think you have to tell lies, but you could organise some leisure activities for yourself, even if it’s meeting a friend for coffee. You need a chat with him and to be quite firm, in a ‘this is what I’ll be doing’ not ‘if it’s ok’ sort of attitude. You’re not being unreasonable, he is.

He is being unreasonable. But it’s very hard to lay the law down when there are children involved.
Much as Paillasson wants her space, she’ll probably be worried about the children, they probably love their weekends with her. I know it’s not fair, I’m just saying it’s not always easy to change things.

Thank you all for your advice. I will suggest once a month as he DOES have other options. I will miss seeing them because they're adorable. However, I will enjoy the peace and quiet and being able to use the weekend to give the house a proper clean and enjoy the sound of silence without feeling guilty...

does he take advantage of you in other ways too.
i think that needs addressing, i know of several middle-aged men who just use their mothers esp; it never seems to occur to them that their mother is an individual in her own right, with a life of her own, and not just there to provide services to them.

It’s too much at two weekends a month in my opinion. If you just did one it would be easier to prepare for with your work commitments. I think that’s fairer for all.
Let him do the other options on the other weekend, the kids will have their ‘just Daddy and Us’ time. He will hopefully learn and have fun and will learn to solo parent in his own way.