I don't like her much, and her daughter is spoilt. I have 3 kids aged 4 and under . I run my own business and usually work away at weekends. I have given myself a weekend off and now she is coming. Also bringing round their Nan who is 85 and has altzheimers.( I'm not really into the Nan much, but I don't feel guilty because at Christmas when she desperately needed care, the family had a stand off and all left her house one by one making a point. She would have been left alone over night, but was not safe and very agitated. I sat with her for 8 hours and arranged some emergency care. I had a 16 week old baby at the time. I am mentioning this otherwise posters will say I am drip feeding if i mention it later )
I just want to sit up here in my bedroom on my own. I think my Husband ought to entertain them because its his family.
50/50 - Yes you shouldn't have to spend precious free time with unpleasant people, but these people are your family. I'd say go out for most of their visit (you will look really rude if you sit upstairs) and return in time to have a quick cuppa with them, saying you had planned your trip out weeks ago etc.
Yes, you are being selfish. But it's not out of order. I wouldn't stay upstairs though, it looks childish and like you're throwing a tantrum. I would calming explain to them that you're sorry but you have prior plans that you can't break, so you're going out.