A sinkhole nightmare

My fiancé and I bought this mattress 9 months ago at our local Mattress Firm. In the store, it felt like a dream - so soft, yet supportive. It started forming giant sinkholes where we each slept almost immediately. We propped it up from underneath, flipped it, rotated it, everything. Still, it kept sagging deeper and deeper. Now, there is a large "hump" between us where the bed still has some structural integrity. Its the only part that does not cause chronic back, shoulder, and neck pain for both of us and we take turns sleeping on it. After several dozen trips to the chiropractor, stretching, yoga, and occasional guest room sleepovers (my trusty old pillowtop), we have decided to throw in the towel and get a new bed. Its not worth it anymore. I may have to go to physical therapy and get a MRI to ensure there is no permanent damage from this bed. Its a shame to have it hauled off since it still looks deceivingly beautiful and comfortable, but it turns into a demon when we go to sleep. I absolutely do not recommend this bed at all and believe it should be completely recalled due to the damage it has caused. As I type this and wait for my new bed to be delivered within the hour, pain is shooting through my back and up through my neck and shoulders and my head is pounding, which seems to be my new homeostasis since last June. I don't think it is a coincidence. For reference, I am 26 and my fiancé is 30. I am a back sleeper and he is a side sleeper. We are healthy, active adults (or we were, anyways). Don't buy this thing.