There's a lot of back story that'll take too long. But to summarise, I'm the older sister,arrived with a number of children. Younger sister is single and has recently (a couple of years ago) had some fairly serious health issues. Totally fine now. We get on ok, are a close family but sister and I aren't very close, we are very different characters and there is a lot of 'water under the bridge '.
Because of this water, DH isn't her biggest fan, but he is welcoming to her and was very supportive during her illness etc.
Anyway. We were hosting this year, sister and my parents (they love 5 mins away, she has a room there but lives elsewhere).
Parents hinted that she would like to stay with us Christmas Eve, I said that wouldn't work as we don't have the space. To be honest, we also don't have the kind of 'easy' relaxed relationship where I would want her to stay over if not necessary, I knew that we would all be together from the Sat through till Monday anyway and DH and I could do with time to decompress without her there.
So we have them round on the Saturday for drinks etc, halfway through she asks again if she can stay over (but in a really wheedling tone, it was very obviously done in front of the kids and my parents to make it harder to say no). Again, I say that won't work for us for various logistical reasons.
She got tearful, disappeared for 10 mins or so, then we all carried on. Then she asked me to go elsewhere with her for a chat away from DH etc, and basically had a bit of a tantrum. A lot of tears, and accusations of my being cold, closed off, unsupportive, she might go to her grave without seeing any children opening stockings etc. Eventually I cave, as I always do. DH overhears, and says in front of my parents that this always happens, tears to get her own way. I beg him to just give in for my sake, as the tension and inevitable recriminations on me are too much to take at Christmas. Which he does, gracefully. Tells her it'll be fine etc.
Dad is looking disapproving (of me), she is still sniffing, telling me I'm not a good big sister etc in effect.
Christmas eve, very tense, feel like shit all day. Eve comes, she says that she won't stay as she can tell she isn't wanted. I suggest coming first thing to join in stockings, which she does.
Day passes ok, the vibe is still very much that we have done her wrong.
So today we are doing our own thing, she goes home. DH and I decide last minute to take kids to a boxing day thing in the morning. She hears, sends a sarky text message along the lines of "thanks so much for my invitation etc". And then asks whether "all that tension yesterday was all because her emotions were triggered 🤷"
I am so in the FOG in this relationship that I don't know whether I am a bad sister, DH is a bad BIL or whether her behaviour is unreasonable. I'm not strong enough for AIBU as this pattern has been a regular occurrence in my life. What do you all think?
Parents are being very short with me today so I think I'm on the naughty list there too.