Are we wrong for not inviting my MIL and SIL to our micro wedding ceremony?

OP, stay away from his mother.
This is not on you.
This is his choice.
His mother created the situation allowing him to be abused and to live with his aunt.
Easier for her to blame you than take responsibility for her actions.

If I was your mother I would hate you marrying into such a mess.
Be careful.
Leave his family to him.
This is not for you to fix at all.
Stay out of it.

@JanineR - ignore all the people on here who clearly haven't read your updates, or are still being wilfully obtuse to what you are saying. He clearly doesn't want his abusive mother (and allowing someone else to abuse your child is abusive) to be there when you sign your marriage licence.

All of these mothers to boys who are talking about how upset they would be in your MILs position and blaming you for not doing more when it is your fiancés decision not to invite his abusive mother sound as bad as your MIL. I feel sorry for the future partners of their sons.

You have done more than I ever would in the circumstances you describe to facilitate her being there, even to your own detriment (offering to get married later for the bigger room, offering to give MIL your sisters place, even feeling bad enough about it to post on here).

Given what she allowed to happen to him as a teen and how she has behaved towards you in the past and now over this, I would be rescinding her invitation to the reception as well!

I would really stop putting any more thought into it now. Your fiancé has made his decision. You are not in contact with her anyway on a day to day basis (which it something it sounds like you should be grateful for), and I'm sure his aunt, who sounds like the only sane one in the family, knows it isn't down to you, so forget about it and enjoy your day.

I wish you all the best in your ongoing mission to completely separate your soon-to-be DH from his birth family. With any luck the fallout from Operation Wedding will cause him to go No Contact with those other women in his life, his mum and his sister, and then he'll be All Yours.

Nah fuck her. Parents who knows their kids are abused and do nothing don't deserve a front row seat to their kids milestones. She's lucky she's bloody invited at all.

'That’s probably why his MIL wasn’t at the top of my mind when we were choosing witnesses for the wedding ceremony.'

Why do you think YOUR relationship with them matter?

As long as they didn't murder your mother or something you dont have to like them and they dont have to like you, stopping your partners relationship with them over your feelings is wildly controlling (if it was a man saying his fiancees mam cant come because he doesn't like he much, we would talk about red flags, isolating and it being a sign of abuse).

He is his own person with his own family and own relationships with them that long pre-date you.

I could not imagine for one second telling my DH his mother or brother could not attended even though I have had issues with them (hell we didn't talk for years) but they are HIS family and HE has a relationship to them.

He was never close to my family either, he has anxiety and avoids getting to know them like the plague... damn sure I wouldn't let him tell him who he 'picked' and who should be invite though based on him not caring about MY loved ones.

Just wow.

OP, this is the kind of MIL you will always have wronged. You could switch the ratio so both mums and his aunt, but his mum will never be a good mum or MIL. So yes it was his choice and also guaranteed to upset them, but they will be permanently upset.

Of course it's unreasonable to pretend your partners own mother wasn't in your mind when thinking who to have at your wedding. However your behaviour pales into insignificance compared with the wet lettuce you're marrying who didn't bother or lacked the gumption to insist. If I were you, I'd take careful note. Because how a man behaves as a son and the kindness he shows his mother is often a really good indicator of how he'll behave as a husband.

But from the OP, sounds like the MIL was already alienating her?

Imagine not protecting your child from your husband's abuse. That is what OP's MIL did when his step-dad abused OP's DH. The aunt that he did invite let him move in with her to get away fro his step-dad's abuse, so he is obviously closer to her than to his own mum.

You are being unreasonable and selfish.
I can’t imagine that your finance is too happy with this inequality and it won’t bode well for your marriage to put a rift between a mother and son.

This with bells on 👏
It is really hard for people from dysfunctional families to articulate it in a way that others understand, especially when the 'its family...you only have one mum' brigade come out.

Hopefully, OP won't let her child's step-father abuse her child like her MIL did with OP's DH. The aunt that he did invite actually took him into her home so he could get away from the abuse.

Or alternatively, did you let him because you actually don't care because you think she's a shit person and you were fine with her being upset? If so, then own than and don't scrabble around trying to make peace. If you're going to take the approach that you don't care about her, you have to then actually not care!

If your mum is going and his is not, that’s really awful. The poor woman.

NRTFT. You either have a legal ceremony (with just two witnesses) or a service where a couple of more guests makes no difference. If my DS was getting married and I wasn't invited, I'd be upset.
DD and DIL had a huge wedding which cost six figures. None of those guests know they married in a legal ceremony a couple of weeks before with just myself and DIL's DM in attendance. Why did you tell MIL you were even getting married if she couldn't come? It sounds like there's no good reason for not inviting her, other than to cause hurt.

If your mum is going his mum should be going too.

OP, why did you let your DP do this or (of you genuinely didn't realize) how are you dealing with the fact he did this?

I don't mean not invite his mother, I mean blow up your wedding and cause you personally all this stress. Who cares if his mother is upset and whether that relationship can be fixed, you are upset and stressed.

A decent partner would not have done this to you. You may not know his mother well and possible extremely naively thought she would be ok with it, he most definitely knew she'd flip out about it. I'm suspicious he wanted to send a message to her to be honest but that's speculation.

A good partner would have either said 'I would prefer my aunt but it's just a bit of paper to be and my mum will flip out and cause us a load of stress, so let's go with my mum' or 'I realise that I'm not ok pretending to my mum that we're close and that I'm ok with her, but I don't want this to cause a storm around our wedding so I'm going to tell my mum now that I don't want contact with her and not mention anything about this witness thing'.

What he chose was him having the person he wanted there, a very upset mum, a shadow that will always be over your wedding day (for you maybe he doesn't care!) and you being stressed and upset. He got what he wanted at your expense (and his mum's expense but she sounds like a terrible person anyway). He's meant to be in love with you and centering you, but he put himself first.

Have you talked to him about this? Your focus seems to be on fixing the mess he made, but the bigger issue is he decided to make it.

Or mention it in the opening post.

"I'm sure MIL understands that she's not being asked to play a traditional role for a valid reason"

Not saying this is right, but it is very unlikely the MIL will "understand". I don't really know anyone who would admit to being a shit mum and be OK with her sister taking her place at her child's wedding.

I just keep reading these posts..... We just invited who we wanted and thought not for one moment of the brother who's been close your whole life or the grandparent who looked after you etc..Just prepared to hurt them and exclude them at the drop of a hat.. Honestly i just fucking despair of how selfish some people are now

I think DP must take charge of this situation. He needs to tell his mother that he made the decision and to stop transferring blame onto you. I'm sure MIL understands that she's not being asked to play a traditional role for a valid reason

The no contact decision may soon be taken out of his hands.

I’ve got daughters but if I had a son I would be devastated not to be invited to his wedding.
How would you feel in these shoes, OP?

Well obviously she was intentionally excluded so I'm surprised you're surprised by the reaction.
Not saying it's the wrong decision she sounds horrendous bit your fiancee has made a right pig of it and should bare responsibility or just go proper no contact and remove the drama altogether