Thanks for all the awesome replies guys!
They've been here for a few days now and I personally don't think she drinks in an alcoholic manner. They do drink on every occasion, but I don't see the signs of alcoholism. That said, my mum did accuse her of being an alcoholic because she kept getting into drunken arguments with mum then 'forgetting' what she said. Her husband is quite a big drinker. He doesn't ever actually get drunk, but does consume more than her. I think being around him probably influences her to drink more.
She can't seem to get the complete 'no drinking' thing though. She was drinking a cocktail yesterday and said 'This is lovely! try it!' I said 'I don't drink' and she said 'You can still try it though!'
