I need help with my food addiction?

I'm only 13 but I'm obese 190 at 5'4 I've been dieting ever since I was 9 and I always fail I need help but I don't know what to do I cry every night because my stomach hurts if I didn't like exercising i would be 300 pounds I always get this feeling to eat bad food so I go to my kitchen and eat, eat,eat.... It's not like I'm hungry but when I get the feeling I feel like eating snacks like cookies cake chips or what ever junk I have in my kitchen, I have a single mom so she doesn't have time to make me dinner she always just gets fast food or orders pizza if she doesn't do one of those she won't get anything so I look in my cabinet for food to eat and all I see are the bad snacks it's not like I eat one snack I eat like 3 of the same thing until my stomach hurts bad maybe it's because my mom is obese so I got my bad habits from her. I just need help I want to be healthy and cured by high school... But I don't know how to break a food addiction? Don't tell me to get rid of all bad food because I don't buy it my mom does and if I told her not to she would say "no because u don't have to eat it, it's for ur brother" and I can't just change to healthy snacks because I'm addicted to bad food not healthy food and they're two different things thanks