You take good care of your stomach issues. I know how painful that can be! I had an ulcer attack at the end of March and had to eat bland for two months. It was challenging and of course boring.
I kicked the soda habit quite a few years ago. In fact I think I was about your age. It makes a huge difference when you let it go. You'll have a much easier time getting the weight off if you stick to water and tea. I like to make iced green tea in the summer and I sweeten it with Agave nectar, because it doesn't affect your blood sugar but it's just as sweet as sugar so I go easy on it. It's very refreshing! You could also make iced tea from all sorts of flavored herbal teas, like Raspberry and Peach tea. They're all great and tea has no calories.