WIBU for cutting MIL out of our lives for comments she made about my 13 year old?

[DefinitelyNotAStepfordWife]

I'll start by stating that I can't stand the woman. I barely tolerated her for my partner and kid's sake before this and already wanted rid of her. There's no hiding that. Pretty sure she hates me too but I really don't care at this point.
On to my question: MIL came to stay over Christmas and asked lots of questions about 13 year old's bf. General stuff, what area does he live, does he treat her nicely, how old is he, stuff like that. Then started asking about if they've done anything yet, even so far as asking if she needs a pregnancy test. She's 13! I know kid's start earlier and earlier, I'm not ignorant, my sister got pregnant at 15 so I know this happens, but come on! She's 13! She blushes when talking about holding her bf's hand and he's only just turned 14 and is in a few of her lessons. It's innocent and cute.
A few comments were made by my partner and his brother about potentially scaring him off but this was said just to tease her a bit and my daughter just laughed and told them to shut up. My MIL then felt comfortable enough to tell my 13 year old that she needs to be careful how much of her new make up she puts on so she doesn't look like a prostitute or make her bf think she's "giving it away". I told MIL multiple times to stop sexualising my daughter but was repeatedly ignored.
Another time, Christmas day, me, my partner and MIL were talking about how the kids were getting tired and need a rest as they were all getting a bit worked up. This was after 13 year old and 10 year old got into an argument. I said how 13 year old shows her temper more when tired and how she was having a rough time at the moment, fall outs with friends, falling behind with homework, pressure of choosing her GCSEs ect, and MIL said "no, she's just a teenager, and all teenage girls are just b*tches". I couldn't believe it! Doesn't help that my partner won't say a word against her, even in defense of the kids.
This is after years of attention seeking from MIL and a lot of nasty comments towards me but this really is the last straw. So AIBU if I tell my partner I want her nowhere near our kids?

Is your partner DD’s dad or stepdad?

Why does your 13yo child have a boyfriend?

Yanbu.
Your partner comes from the dregs of society clearly.
What a vulgar way to speak around children.
Your partner is no better than his mother.
Your poor children.

You are being really fucking dramatic tbh

FFs!

Because quite a few 13 year olds do, as the OP says it is all innocent

She sounds horrific. I’d be horrified if my MIL spoke about DS and his girlfriend in that way. It’s inappropriate.

Why not?

Really dramatic that Nan told 13 year old she looks like a prostitute and is giving it away?
Maybe you're being really under dramatic

OP I wouldn't have her around my daughter

Your 13yr old should not have a boyfriend. On what planet do 13yr olds have boyfriends??

Lol @ 'why does your 13 yo have a bf'. Presumably because she fancies him and wants one? Asking if she 'needs a pregnancy test'? Haha. I'd laugh it off. Say 'no, the twins are due in April.' 🤣
But you obviously despise this woman so just ignore her. And have very little contact.

Exactly. But yet I'm being pointed out.

Only on MN are 13yo have partners,relationships, sex and it's all fine and dandy. Not saying op dd is, but have seen countless threads where young kids are in relationships with boyfriends staying over and it's ok.
I would harshly judge a parent that allows their 13yo child having a boyfriend

He's not her biological dad but has been there since pregnancy and she calls him dad and he loves her the same as our other 2. I will come to his defense that there is a lot of childhood crap involved that makes it so he struggles to say no to his mum and her attention seeking makes it difficult for him and his brother to see through the bs and realise she's just a vile sack of nastiness.

She’s from a different generation, I think you need to take that into account. I also don’t think this warrants ending contact over. This is your husband’s mum, you only get one, I wouldn’t chucked it over this.

Perhaps she’s being extra vile to DD because she’s not your partner’s bio child?

Like I said, it's all innocent. She isn't allowed her phone upstairs so I know they aren't sending pictures and they don't even see each other outside of school. Of course I'm not ok with anything sexual but she is growing up and finding her identity and I respect and support that.

Seriously ....why not ban them and see how long it takes for everything to be hidden and secretive it didn't work in the 50s why should it work now?

It all sounds very dysfunctional and lacking in social graces, very odd behaviour

So not a ‘boyfriend’, just a friend that is also a boy.

And I am equally puzzled when I see this attitude on here.
When I was at school in the 90s there were plenty of 13 year old couples, it was very normal and usually unproblematic, and usually pretty chaste (with the odd exception). I didn't have a boyfriend until I was about 15 and I felt it was quite late in the day! But I can't imagine growing up and thinking 13 year olds don't have boyfriends? They do and it's nothing new?

Surely you dont really think two thirteen year olds of the opposite sex can have a totally innocent long-term bf/gf relationship? It's not going to happen. Sex at some point will come into it.

And yet here you are calling him a ‘boyfriend’, and your DP talks about scaring him off. The whole lot of you are sexualising this friendship.

Exactly!!