Yes, mentally switch off. Don’t give them any information about what you are doing and keep conversation light.

Each time they make a comment, smile sweetly and say oh mil/fil sorry that you feel that way about (whatever they are criticising in your life) me and dh are happy about it...and follow it up with something like that is what makes the world such a wonderful place, everybody can have their own preferences about (name situation she is bitching about)..and then give a head tilt and raise an eye brow and say mil don't you think it would be like living in a dictatorship if we all had to be the same and think the same and worship the same and parent the same etc

And keep repeating the above each time they bitch about something ...it will drive them.mad that they aren't getting to you and that you have a comeback😁

Don't actively have anything to do with them, don't give them any information to disapprove of. Don't suggest any visiting, although you would probably have to respond if they contact you. If it was anyone else, you'd go NC ...

I’m hesitating to recommend a bit of reading to you, on the site outofthefog. It might well make things worse, when you read other folk’s similar experiences and some of the effective techniques they use (like ‘grey rock’ and ‘low contact’).

But in the end, you’re entitled to a good calm family life, and to role model sensible non-toxic family life to your kids. However ‘used to it’ your dh might be.

Does he criticise your children in this way? Adults can cope with this by either refusing to engage or challenging each comment. Children can’t.

I say this because there is a similar personality in my extended family, he has been openly critical of one child in particular, parents had to confront him and contact has been significantly reduced.

You could either be "bright and breezy" in their company, which would be hard given how difficult they sound or speak to them directly. I don't do bright and breezy so would have to have it out with them.

Would DH go completely NC with them?

How much time do you spend with them.
Does your dh challenge them?

I'd be less inclined to be bright and breezy. If it were me I'd be firm and shut down every time. "We aren't interested in your unsolicited opinion, please stop". Then change the subject.

If they keep at it, I'd honestly be asking them to leave. What do you or your family get out of the relationship?

Urgh so familiar
Whatever I did it got uglier (I the dh in your scenario)
Sympathy and luck to you x

I think it's a bit unrealistic to say things like that KM99 in RL. I know we all write that we would say this and that on here but in reality it's different and not so easy.

This situation is a complex one that needs addressing properly by sitting down and talking about these people make the OP feel. It may work or it might cause them to back off completely. No skin off the OP's nose either way.

My FIL is an utterly repugnant man. Bigoted, homophobic and just generally an abusive arsehole.

I ignore him, just don’t engage or I’ll lose my temper.

Thankfully they live thousands of miles away so we don’t see them often. The downside is when they do visit it’s for weeks at a time.

BIL is a chip off the old block and I lost my temper when they stayed earlier this year. I refuse to let my beautiful husband be treated like shit.

Interestingly BILs behaviour improved measurable after I threatened to rip his fucking head off perhaps give that a go?

I would be vague, don't encourage visits, put them off and carry on pulling him up on his rudeness.

Cut the visits short if need be,

My MIL is like this. No matter what it is, I/DH do it wrong. It’s my fault the kids have homework, my fault the U.K. grocery stores use lots of packaging (they THANKFULLY live on another continent), plus all the usual stuff (kids, house, car etc).

Anyway, I leave when they come. Like I book flights and go. If that isn’t an option, can you be out on errands/plans every 2 of 3 visits, OP?

My DH says I need to just shrug and say ‘that’s your opinion, but it’s not mine’ when she says stupid stuff. It’s hard though when it’s a personal attack so I empathise!

Following with interest and trying low contact. Unfortunately, it does affect the children. One is close to her cousin but they interfere so much, it encourages teen dd to rebel against us and to dh, in particular

After 17 years of this bullshit, I would tell my husband I'm DONE with it. If he wants to visit them, that's fine, but I would no longer have anything to do with them.

I can relate. I'm not sure whether how I cope is the best method or not, but I just don't see my PIL. or see them as little as possible. At first I felt guilty but after many years of biting my tongue, then switching off mentally at every gathering, I realised that I don't have to be around them. DH can go see them as much as he wishes, I don't have to :) it's quite liberating. Life is too short for being around people who make you feel miserable, whether they're in your family or not.

Difficult, after 30 years I’m still working on it. Actually I ended up loving MIL very much despite her judgemental ways. She was just such a character. I challenged her if I disagreed which I think she was fine with. She sadly died last year.

FIL is another kettle of fish. Very difficult, hates being contradicted even when he’s absolutely wrong and we make a very gentle correction. He’s also massively demanding. We cope by rolling our eyes, sticking together and leaving if he’s really getting me down. Sometimes he is ok.

I have on occasion said that we shoydrop a subject as I don’t want to fall out with him. When we were all younger I might have said something like, ‘Oh I guessed you might feel that way,’ or ‘Ah well, we all do things differently.’

As you can tell I’m not a pushover but honestly over the years they have upset me a good few times. They NEVER apologise but sometimes they will act a bit sheepish so you know they know...

Anyway easiest option is to make your excuses and leave if they are being rude. Not easy.

Could you both challenge them in a low key way - have a few responses such as 'that's very rude' or 'I don't think that's a good idea' or 'we won't be doing that, thanks', or 'we don't agree with that', delivered in a firm but reasonable voice. Over and over again. And reduce contact time!

The bit about 'not wanting their disapproval' resonates with me. My folks are one giant ball of negativity about the minutest of things

I have had some success on pulling my Mum up every time and she now shuts up about some things

But disengaging ux really the only option

I'd just keep visits short, few hours at most: & limit them. Add a lunch in to make less talking time. Keep it vague & superficial, don't give info as it's amunition ('we haven't decided yet/we havent thought about that yet) & if it's getting nasty, leave, instantly.

My mum is like your inlaws - she just can't help herself. I used to bite my tongue and have a good rant when we were alone again. These days I laugh at her, and that really flusters her and puts her on the back foot. Whatever we say, eg: "Mum, we're going to Cornwall", she will give a negative response: "I don't like Cornwall - no trees". "Mum, were thinking of going to Canada." "Okay if you like trees I suppose." "We're going to Krakow." "Rather you than me!" Honestly, it's never ending. We moved last year and there's lovely open parkland to the front of our property. Mum asked if our dog had settled down and I said "Yes, she loves it. She takes herself off around the parkland." My mother's response "Oh, you call it parkland do you? I think of it as wasteland." Classic mum. I just laughed and said "Charming! Don't worry, we won't force you to visit us on our wasteland." I don't think they even know they're doing it half the time, it's a reflex action. She must think we live very boring lives as we share very little information with her now.

Why would you want your children to have a relationship with such people?
My father was awful to me growing up. Just because someone is related to you, doesn't mean you should have a relationship with them regardless of how they treat you.