They MUST get her 'Dont's for Wives 1913'. It's a little red book that you can get from Waterstones. It's normally on the counter by the till. My Mum bought it for me at Christmas and I've just given one to my friend whose getting married next month.
I'm sure that she'll be grateful to know that 'Nothing pains a man more than finding only a cold welcome when he brings home a chum.....' or 'Don't grumble because your husband insists on wearing an old coat in the house....'
It's a wonderful look at how things used to be and will make both her and her husband smile!