How do I stop eating between meals and eating food that's bad for you?

After almost a year of waiting and postponed dates it looks as if I am close to get my gastric bypass surgery. The biggest problem now is that have put on some weight since my first doctor’s meeting in March (due to depression medication and bad habits) and I need to reduce my weight with about 10kg before the end of February when the surgery is most likely due.

I should be motivated like hell, but I am not. Probably because they have postponed the surgery four times now and for each time I have died a little inside (almost true) and lost hope and motivation. Hopefully I will get day and time this coming week and I think as soon as I get it, I will be back with full motivation again.

My problem is that I love food, I love sweets and unhealthy food. I have created a bad habit and I eat a lot between meals and I don’t take time to cook for myself. This is something that will and must change after surgery, but I need it to change now, before surgery.

How can I do it? Do you have any tricks and tips to share?