Changed username for this. It's going to be a long one but I think the backstory is important.
DH has 1 DS. We all live in the UK, but they are from one European country and I'm from another. DSIL came to the UK some years after DH. As he had done previously, he introduced her to all his friends and helped her settle in. I moved here a year after and we all enjoyed a very good relationship. The 2 of them are very different but we enjoyed socialising together, but DH has always been aware that she complains about his ways with common friends and (intentionally or not) creates distance between him and his friends.
A few years ago, I fell pregnant. 6 months later, SIL found out she was pregant too and, although it was unplanned, she sad she was very happy to go ahead as a single parent. When DC1 was born we moved to a larger house and when DN was born SIL moved round the corner from us. Because we live so close, we ended up spending lots of time together and it seems like she expects us to invite her along with us anywhere we go, but never invites us when she meets her own friends, and often meets our common friends without asking us to join, even when we introduced her to them ourselves.
The first Christmas after our kids were born, she decided to join us in my home country, even though we hadn't really asked her to. She said my family had previously told her she was welcome any time, and she didn't really have anywhere else to go (their parents both passed away). She had just lost her job so we paid for her flights and sorted out accommodation for her, and she tagged along everywhere we went. It was fine but obviously changed the dynamics. She then started messaging family members of mine directly, to the point that she invited my cousin over when she was visiting the UK and we were away, and I only found out from my cousin even though I see DSIL several times a week.
DSIL is always complaining about how hard things are for her and never really bothers to ask how we're doing - she often says we have life easy as there's 2 of us, with 2 stable jobs, my family for support, etc. We can't talk about our DC without her comparing with hers. After months of my DH getting resentful about (what he sees as) the one-sidedness of the relationship, he spoke to her about all of this and asked her to keep some distance from family and friends in my home country, and not assume that she can join us there, because it's the only aspect of our life where we have our own space. She took that really badly and the relationship hasn't been the same since.
Last year, I fell pregnant, the due date was Xmas Eve and we came to my home country to give birth and spend a few months. DSIL mentioned that she'd like to come spend Xmas with us but we said that wouldn't work because we wouldn't be able to 'host' her right when we'd be giving birth and trying to settle in with our toddler, and suggested she visit for a weekend in Jan if she didn't have leave from her new job. She said that wouldn't work for her as she had other travel plans and that her Xmas was ruined as she'd be alone. We've been in touch via videocalls regularly and now DH messaged our date of our return and asked if she'd be free to meet as soon as we get back as we'd like to introduce her to DC2. She replied that she can't wait to meet DC2 and see all of us again but will let us know when she's free closer to the date. And that she wants to reiterate that this doesn't change the fact that she's going to be 'the last' to meet her DN after all the 'outsiders' have been introduced over these months and she can't believe we did that to her, telling her that we didn't want her in my home country and didn't let her choose her own travel dates or consider the fact that it's hard for her to travel for just a weekend alone with a toddler. As a side note, a common friend just told me that she's going away for a weekend, somewhere else, a month before we return to the UK.
I'm quite upset that she's made it all about her. We used to be very close and I'm pretty offended myself that she didn't come visit at all in the 3 months we'd have been here.
So, if you got this far:
YABU: cut the woman some slack, she's got a lot going on, she has a right to do and say what she likes with people she knows, and your DH was insensitive trying to cut her out and tell her she's not welcome
YANBU: DSIL should realise it's not all about her, especially when you were having a baby, and that she can't only take from this relationship