Accept that the weather changes and you have to do some extra things in the winter to keep yourself from gaining weight.
Eat lots of fruits and veggies~ They are low in calories and help to fill you up on cold winter days.
I notice that the colder it gets the hungrier I get. This is an unfortunate happening but it can be combated with some soup.
Cold Winter Days Call for Some Hot Soup
On cold winter days I make my special vegetable soup with low sodium veggie broth, carrots, sweet potatoes, cabbage, an onion, some garlic and some Asian noodles. I eat it all day long because it is so very low in calories.
Another good thing to do in the winter months is to have some distracting things to do. I craft, knit, crochet and exercise. TV is never a good thing, especially in the evening- find something else to do.
Exercise: Try some fast walking- heel to toe- just like the fast walkers do
The exercise part is a little more difficult this time of year. You have to be creative. I take short, fast walks multiple times due to the cold weather. And when I cannot take the cold (today was 25 degrees!) I go to the basement on my treadmill and elliptical. I made it a good place to be. Put a TV in front and before you know it- you forget that you are exercising.
Do not give in to the wrath of the winter months. Get out there and dance! Expect that it will be harder to want to exercise. Expect that it will be harder to just get outside, but do it, even if only for a few minutes a day. Staying indoors too much can depress you. You need to get some fresh air and sunshine.