Chest and Back pain from heavy boobs.

HELP. I've always been bigger chested, when I was smaller my breasts were still a triple D. But I've gained A LOT of weight since my "skinny days" and am currently trying to lose weight again. My back constantly hurts, my joints and spine crack all the time and my chest sometimes has a lot of pressure in it. Recently I realized my breasts are bigger than before and I guess I've started gaining weight in them...

How do you all deal with this type of pain? What helps!?