My sister has (had?) bad teeth due to a few different things. She ate a bunch of iron as a kid and had to have her stomach pumped which still turned her teeth black and caused issues, then she struggled with addiction as a young adult. It's nothing to be ashamed of to have bad teeth due to an illness, including addiction, which is an illness - in fact if that's the case good for you for overcoming it.
If you have a hard time eating raw veg, you can still eat tofu, nut butters, and things like tomato sauce on pasta. You can eat hummus, babaganoush, and tahini. If you sautee squash, zucchini, onions, eggplant, spinach, they become pretty soft and mushy. You can also make veggie-loaded soups, and eat well-cooked beans and rice. Even if you don't like juicing, if you crave those raw veggies you can make mixed juices and smoothies with kale, carrots, beets, etc. Naturally soft fruits are bananas, plums, seedless grapes, mango, and apricots or peaches. You can integrate limes or lemons by squeezing them into sauces or other recipes, and make your own fresh-squeezed OJ or grapefruit juice at home.
Apparently there are vegan powders you can buy to put into juices or smoothies that add fiber if you still feel this would not provide enough fiber in your diet.