Janreb - we are a bit like this, too; but not as bad as my sister and her husband. She has to watch absolutely everything she eats - he, on the other hand, loses weight if he doesn't eat enormous quantities of bread, potatoes, cake, and chocolate. It is just his metabolism, of course. I have hypothyroidism and, even though it is under control, I find losing weight extremely difficult. I really sympathise with you - it's just not fair!
We (husband and myself) decided to start our diet a couple of weeks ago, both want to lose a stone. We eat almost the same things, only difference being he has sugar in his coffee, I don't. He also has full fat milk and I have skimmed. He also has two weetabix at night to take his tablets with. He doesn't exercise and I walk at least 5 miles every day with the dog. So how come he has lost 3lbs and I have only lost 1/2lb? It just is not fair!!