I used to do this after I had a really great week, my mom and I would go out to a restaurant and eat what we knew we shouldn't.
What I've found that keeps me from eating the things I know are bad for me is I build a weeks worth of meals at a time. I take usually about an hour to an hour and a half to figure out the recipes every Friday and then we go grocery shopping.I don't buy anything extra at the store.
I've found that looking on pinterest/WW/here for dessert recipes is an excellent way to stay on track too, that way you don't go on a sugar crazed binge.
I honestly am to the point where I do not miss fast food or really fatty desserts ever. I'm not sure if everyone gets to this point, but I would imagine you do. If I want a cheeseburger, I let myself have it. I'm really strict about my points though. I weigh every single thing and track every single thing that I put in my body.
It takes a lot of self-control sometimes, but YOU CAN DO IT!!!! Also, congrats on reaching your 5%!