My wife of 12 years is angry because I don’t want to go on holiday with her elderly parents. The thing is, we have already been away once this year, have another holiday next week with grandkids and another for me and her at new year. She doesn’t even have to work as I give her money every month, too.
It’s not just down to cost either, as I can’t stand her parents. They constantly bicker and have really bad and embarrassing manners. Wife is saying that they are old now and may not have many more holidays but her mum goes on about 3 or 4 holidays every year anyway. I feel like I am being blackmailed. Am I being unreasonable?
LemonVibe 
It doesn’t seem like you’re being unreasonable. It sounds like this is something that is brought up often and causes strife between you and your wife.
I recommend talking with your wife and maybe suggesting that she goes on these trips without you. If she is aware that you do not get along with her parents, I can’t imagine why she would want you to suffer. Suppose it was the other way around. Would you be upset that she didn’t want to do something for you?
Marriage is about compromise, but it’s also about knowing each other’s limits.
Talking it out will be the best thing, and hopefully she will understand and go on these trips without you.