BIL left his wife and wanted to stay with us I said no.

[Cantmindmyown]

DH thinks I’m wrong. I don’t want to facilitate this as I don’t agree with BIL leaving her when she is vulnerable (breakdown due to a late loss).

BIL turned up asking to stay at ours ‘for a while’ and stated that he just can’t cope with her depression and neediness anymore that he feels suffocated. MIL has been on the phone saying we need to support him. Nobody is concerned about his wife though ??!! I told DH that no - he can’t stay here he needs to go home and support his wife.

Should I message her to see if she’s ok ? Will that make things worse ? Or does she need to know she has support and someone who actually cares how she is. I don’t want to embarrass her that we know they’ve had problems but equally I don’t want to do nothing .

I think you’d be unreasonable to tell your DH his brother can’t stay for a couple of nights, just as he’d be unreasonable to tell you a family member can’t stay. You don’t have a reason beyond disagreeing with his choice, so I’m assuming there’s no concerns about him staying (like he’ll wreck the place or something).

YANBU to support your SIL.

Imagine it was your sibling that turned up and your DH sent them away.
It's obviously taking a toll on your BILs mental health too and he needs support from his family. There's nothing stopping you from reaching out to your SIL and supporting her, you can do this without preventing your DH from supporting his brother.

The only thing he’d be getting from me would be a boot up his arse.

Well, that might be how some people process their grief but it doesn't make it OK. And many more people just behave like that because they're not very nice people.

After reading all of the updates, just wanted to say you sound like a lovely person. Your in-laws are lucky to have you

I get that people grieve differently, but it certainly doesn't sound like grief to me. Sounds like a nasty arse of a man who is void of all compassion. His wife is understandably broken, and he's too impatient and heartless to be there to help her through her trauma and immense grief. I can see why you didn't want him to stay. I can also see why you're now letting him stay for a night or two, I hope you can get through to him the magnificence of what his wife is going through, and how he can learn to be understanding, sympathetic and compassionate towards her. Ask him how he is feeling about the death of his child? Try to see how he views it might help how you talk to him.

Some people don't see a baby as a child if it dies in utero, so don't grieve. I'm personally baffled by this, but it does certainly happen. Perhaps he's like this. If he is, then hopefully you can get through to him on what his wife is actually dealing with. Not only this, she's given birth to her dead child, that in itself is just horrific for any woman to go through. His lack of understanding and compassion towards her is mind-blowing to me.

If you can't get through to him, he's just a plain nasty, heartless bastard.

Does she have local support?

Support both of them and make it clear that you won’t take sides. Your DH can be there for BIL to offload and you can be there for SIL. I would also suggest you don’t share what they tell you with each other in case it somehow slips out and causes trouble. They each need somebody they can talk to in confidence. If it truly is the end for them there will be little you can do but at least you will have tried to help.