I know it's a stretch to ask you to switch from that way of living and that diet to "oh have a salad", but just try this - use the "swap" method. Swap your afternoon chocolate bar for say.. a few strawberries instead - or make a smoothie with *some* chocolate and add fruit like a banana or blueberries. Slowly familiarize yourself with fruits, and then vegetables. Instead of peanut butter on wholegrain toast, try avocado or tomato with pepper. Instead of doritos, make healthy tacos with salsa, a bit of cheese and fill it with some lettuce, cucumber, beans, etc. Add veggies to your pizza, cut them up small so you don't notice them as much if you wish. You need to get in a habit of eating veg!
Your body will thank you for it in the long run