Pity Party

I lost 31lbs over the summer now im gaining it back. My motivation is totally gone. I don't exercise or eat right. I sleep as much as I can. I can see the weight gaining up on me and I can't stop myself from going to get fast food. I always tell myself this is the last time, but it never is. I kick myself in the *kitten* every time I do bad, but it doesn't sto me from doing it again. I was so into working out at the gym, and spent money on a HRM, Fitbit and apps for tracking workouts on my phone. Now nothing seems to matter. Even when I tell myself it's for my daughter I think eh, she's too young to remember me like this, I can start on monday. Anyone know how I could take on the world one day then the next hide under my bed. I'm on meds for depression could they not be working anymore? Any advice would be great!