It is unfortunate, but many women seem to have this problem as they go through menopause.
Hormonal changes can make you more sensitive to carbohydrates so you put on weight quicker and find it harder to lose!
I would suggest having a look at either the GL diet or the Paleo diet, these both help to control carb intake and can help, often very effectively, to reduce weight.
For some women, going through menopause slows down thyroid function leading to weight gain, so it is a good idea to ask your doctor for a thyroid test as well. Exercise is important, so try and fit some in every day if possible—even a brisk, 15-minute walk can work wonders!