Hello Julia, unfortunately, I know many persons with the same problem that you are facing, and I know that it's really hard to quit smoking. There are many methods, but before anything, you have to want stop. This wanting has to come from you, otherwise it will not work.
Firstly, why don't you try to look for a smoking quit group, like you, that want stop? It's always good to have people that understand what you are facing, and shear their experience about what they are doing to stop smoking.
Secondly, you could do sports or do one hobby that you like to do, than you will be distracted with other things and will be good to your health. Many people stop smoking by doing it and you have to know the risks that smoking brings to you. You can die, and nobody wants it, Right?