Gaining 70 pounds in 7 years is not uncommon, but for a diabetic person is little on higher side.This also may be one of the reasons of your aches.
In long standing diabetics
peripheral neuropathy is one of the cause of aches and pains.
Start
aerobic exercise to the extent you can tolerate at present and increase to little higher level, it will also keep your sugar in control.
Get yourself investigated at the same time thoroughly including
thyroid function test, and see your doctor with the same.
Try diet full of protein and fibers, less of calories and fat.Avoid fast food, drinks containing
carbohydrate even diet drinks contain some carbohydrate.
You can consult a dietitian for the same.
Hope you will shed a little weight but certainly not gain if all the other invetigations are normal.