Breakfast bars, mini bags of popcorn, yogurts (I'm guessing Muller Light type things, or Fruit Corners?) and supermarket pizzas won't give you any of the vitamins and minerals you need to feel energetic, healthy, happy and bouncy. I'm guessing you often feel exhausted, stressed and snappy, and then have no choice but to binge on more sugar/carbs or fats to perk yourself up?
Why not follow a simple eating plan like WW (no need for meetings, you can do it all on their amazing app) and learn to change your eating once and for all?
You've got 4 kids. You all need to be eating healthy, nutritious meals.
If you were a size 12 for years then you're probably an "eat to live" type person, so you never really paid much attention to what you ate. But this now is a great opportunity to learn about healthy eating. When you eat things that your body loves you just feel AMAZING. Full of energy, calm, bouncy, unstressed, optimistic, happy... It's not just about the number on your scale or what size your jeans are. It's about your overall "zingy-ness".