Would you take offence to this?

This is the perfect response. Not mean or bitchy just matter of fact and honest. Be armed with it next time she says something rude(if you allow her a next time)

Also, maybe you and your family should start calling her out on her rude comments - every single time, why does she get a free pass? People like this do it bc they get away with it and their victims are usually stunned into silence or too embarrassed to respond in kind.

The cheeky twat. I'd have felt like telling her to get fucked

I'm blaming the STUPID 'threads like this one' it's a stupid addition & is increasing the number of zombie threads!!

Here's my armchair diagnosis - most likely ADHD

She was rude yes, but I'd guess it was more about her being thoughtless rather than being deliberately mean. Either way though it's unacceptable and I hope you picked her up on it.
In your position I'd be inclined to speak to her specifically about this, either a call or in person, whichever you feel most comfortable with. Don't come from the angle that you're berating her, just help her to understand that her 5 seconds of words is affecting you now.
If it's any consolation, I'd guess what she felt was that sense of familiarity and comfort when she squeezed your arm. No judgement, just feeling that she could slip right back into that old familiar relationship even if she hadn't seen you for a while, that everything was just as she'd left it. Maybe similar to her saying 'As soon as I saw that mass of red hair....' etc. I think it came from a good place and when she finds out how disturbing you've found that comment (do let her know) she'll be full of remorse.

Lemonademoney

Why did you resurrect a zombie thread??

Tbh, I've reached an age where I don't tolerate this shit any more. I think I'd have just cut the meeting then and told her I'm not spending time with someone who's so rude to me. She says stuff like this because she keeps getting away with it.

This

Ask her to explain the joke. Paddington stare while she attempts to.

"Oh. I guess I just think jokes ought to be funny and not at the expense of another person." <shrug>

Yes I would feel exactly how you do OP. What a horrible thing to say. She’s not a nice person and I wouldn’t bother meeting up with her again.

When I didn't laugh along she said "Oh no I'm only joking"

The knee jerk response of the bully. Along with 'what's wrong, can't you take a joke?'

I would be interested to know how she reacts when somebody is similarly tactless to her; is she prepared to laugh it off because "they were only joking".
In my experience, they can be very upset.......
I know you were taken aback, but how would she have taken, for example, a lingering look at her own ample frame, followed by "Ooooooh, pots and kettles!", or "You got a refund from the charm school, I hope?"

I like your partner's idea ☺️
She was rude and offensive and, despite it just being her personality, she should not have said anything. Some people don't realise how hurtful words can be and some do just to get a rise or to feel better about themselves.
Feel sorry for her that the only way she can live is by sucking the joy out of others. Turn it round in your mind.

OP,

Awful thing to say and you do not have to accept it.

Avoid her going forward and block her number.

Try not to allow it to spoil your day, even though it would upset most people.

Enjoy your baby, the weight will sort itself out.

Well done @Lemonademoney for resurrecting a post from May 2022!

Absolutely I'd take offence, given offence was precisely what I would have been offered. Unless your cousin lives under a rock she can't be unaware that people don't like being called fat. People with a history of EDs much less so. I can't imagine what could have possibly motivated her to say that other than she's just a nasty piece of work.

Wow! What a nasty person - how does she react if people say stuff like that to her?

I'd laugh it off but it would really depend on how close to her I was .

If I'd always joked about my fat arms before then a a comment about my fat arms wouldn't bother me.

Resilience.

Yes, I would. I might not say much at the time but I would think the worst of them for it.

And we have today's armchair diagnosis of being on the spectrum. 35 posts in. That must be a record.

Some people are just rude.

Not autistic (diagnosed or not).

Just rude. And they try to brush it away as being a joke. It's not a joke and they are being rude.

DM puts her foot in like this constantly. We think she is an undiagnosed autistic. (Several other adults in the family are on the waiting list for autism diagnoses so it is not as
Crazy as it may sound).

I would be upset too OP. However, maybe your cousin is just thoughtless and didn't mean to upset you, like my DM.

I would feel that the only response to her saying "Oh no, I'm only joking" would be to retort "Well, having only had a baby 7 months ago, I'm in the process of losing the baby weight and doing something about my health but....well....you'll always be a nasty individual who clearly with age hasn't learned the lesson that if you haven't anything nice to say, best not to say anything."

Depending on how close as cousins you are that would be....

"Please don't project your own issues onto me."

People are just shit, due to comments made about my fat calves and cankles I never wear anything other than full length trousers or jeans. I own 2 pairs of shorts that I only wear abroad and then I make sure my legs arent in any photos.
Those comments have never been forgotton.