People are jerks sometimes. I'm so sorry they hurt you. I was once 75lbs heavier than I am now (I went from an XL to an X-S, but have gained a bit back), so I know how nasty people can be when you're overweight. Including your own family. (Actually, you don't sound overweight to me!)
Forty-seven lbs is VERY doable, and DON'T let them discourage you! Heck, I lost that 75-80lbs in less than 2 years, without even trying to, and not exercising. (I became pre-diabetic, and simply put myself on a low-fat, low-sugar, high-fiber, all-around healthy diet. In fact, I actually ate MORE than previosuly, never exercised, and, just by doing that, the weight dropped off.) I know you can do it!!!! Listen to your doctor; if they think you should lose weight, do so. It's the leading cause of Type 2 diabetes. Eat sensibly; go for walks every day (great low-impact exercise). I'll bet that 47lbs comes right off.
You will be tempted to cheat every so often. Don't deny yourself. Find some healthy, low-sugar, low-fat recipes, like desserts, if desserts are your downfall. (I used to eat fat-free, sugar-free chocolate pudding, with a dollop of Cool Whip every night). I ate 6 small meals per day, on time, and no skipping of the snacks. This help stabilize your blood sugar, and aids in weight-loss. Get yourself in the habit of ALWAYS having your healthy food available--at home and at work. This way, you won't need to eat bad stuff.
If you lose, then gain a little back, don't be hard on yourself. You can always do it again. I've alwasy said, loing the weight is easy; maintaining it is the hardest part. Don't go on a crash diet, either. You need to learn good eating habits as part of your weight-loss dit, then retain them for life, with perhaps some tweaking (so you stop losing weight).