Am I unreasonable or is MIL

It’s not how anyone saw it except ☝🏻

OP, sounds like you have been hugely overly tolerant of s rude woman. No one would tolerate turning up to collect their child to find them gone with no explanation.
Really rude and disrespectful.
Paid childcare and absolutely no more unsupervised visits.
She sounds unhinged and vile.
I really wouldn't want someone so unstable around my child so stepping back could be wise.

Sounds like there were underlying issues waiting to come out tbh. She hasnt just gone batshit over the text.

I sometimes think people on the forum exist on a completely different planet. Or else we could use some of you lot to colonise Mars when the time comes.

Do you always read things that aren't there? I'd be going to the GP if I were you. You sound unwell.

Is there a wider context here? Perhaps you have different norms within the families. For us things like this are always casual. Did you actually have plans? If so I'm.not sure why you wouldn't just say sorry, will have to be another time we are already booked onto x,y,z rather than send a text later. I've been to pick up DC before and they've decided they're having a sleepover at Grandma's, if we have no firm.plans it's fine, great that they have relatives who want to take them.out and do things.

I think yabu based on this alone but I feel like there's a wider context.

Massive eyeroll.
If it wasn’t relevant, why’d you point it out?
Like everyone else on this thread, you could’ve simply ignored it — but nooo, you had to be condescending.
Noted.

When did this happen OP? How long ago?
Has she had your son since?
Has there been any conversation following the texts?

She sounds like a psycho bitch. Your reaction is totally normal, hers not so.

Children are like animals, they often gravitate towards genuine, kind people. I think they can sense a narc a mile off and I wouldn’t be surprised if this GP isn’t a favourite.

I had a similar situation with MIL when I first started standing up to her after I had been with her son nearly 15 years. No one had ever stood up to her, they just let her get away with being a control freak narcissist for a quiet life. However now they stand up to her too! So now she cries that we’re all picking on her 🙄

Paid childcare is the answer here OP, then you can drop off and pick up as arranged.

I’m one of those kids who preferred their grandparents to their parents.
No tension, no drinking, no arguments, no recriminations, no scolding — just pleasant meals and calmness.
Life isn’t always what it’s cracked up to be at home, but everything is always okay at Nana and Granddad’s.
It was always an oasis of happiness for me and I miss them something awful.

If your arrangement for babysitting is that you collect the child at a certain time then MIL should not schedule activities after that time without asking you if it will be ok. When I look after my grandkids I know what time to expect mom or dad to come and fetch them and I have them ready for that time.

@DJW62

This is all very true and is always the way i think, this is why this situation has upset ne so much. I have no side of my family, just me my father and DS so his family is very important to me.

^^^^^^^

I lost my mum in my teens so was eager to have a good relationship with my mil.

But I learnt very quickly that sometimes I would ignore things I shouldn't.

But you have done that for 8 years?

They don't change (seem to have very little, zero , self awareness).

As long as you're friendly and have strong boundaries , that's the best you can do.

Remember mil ranted off at you ?
You didn't

Mil is old enough to know better but acted like a child.

I do tend to agree. It depends how much you really want to get on with DH’s side of the family.
It sounds like this was only arranged last minute because the cousin was there and why are you only blaming mil when there were also 2 x sil involved? Are you sure mil was really demanding in a bad way and not just pushing a bit to get the cousins together?
We all have to work at relationships if we want them to blossom and were you to take the dramatic step of stopping pil looking after their gc who is really benefitting/loosing out?
I’ve made mistakes, I’ve said the wrong thing on many occasions over the years with relatives but so have they. We talk about it, if necessary, agree a way forward and then forgive and forget.
It doesn’t sound good your mil exploded, sympathies for that, but you also need to ask yourself why and also ultimately if she loves your family and if so find a way forward.
Of course it means you being the bigger person when she has gone way too far, so let her know to her face how you feel about all of this for sure and how you need things to be but not lecturing her with arms folded, using access as a weapon. Who responds well to that?
I hope you sort it out as family are precious, and not just your side of the family.

I’m sorry OP but your MIL is a CF. I would have just taken DS and said sorry we have plans and given you haven’t advised in advance I will be leaving with DS. You need to put clear boundaries in place for people who behave that way. I would also text back and say how dare you send me this text and be prepared to sort your childcare through other means. What a silly bitch! And rude with it!

@DJW62

Mo way would she be having sole care of my child, she's off her rocker & I wouldn't trust her. God alone knows what she's dropping in his ear.

id be booking childcare tomorrow, she'll likely Bleet to DH he needs to be primed what to say to her.

something on the basis of 'Mother, you brought this on by not respecting @DJW62 as Charlie's Mum & went indanely off
of the deep end when she asked if next time you could check with us first before making plans with Charlie. We feel it's in Charlie's best interest to be in childcare & not be subject to you shouting at his Mum'

he must not blame you!!