The title pretty much says it all. Somewhere along the way, my tatas, side tatas, and batwings have all merged to form some super tata that encircles my entire torso.
I have a short torso and sensitive armpit area, so finding a bra to contain all this AND be comfortable is a real issue.
I'm currently in a wireless Cacique that is about 4 inches too big in the band, but it is the only thing that doesn't give me pain during the day.
Any ideas?

NOT laughing at your situation but at your super humerous-Super Tata description. I hope so much that you can find a bra that fits you perfectly and comfortably 
Oddly, my sports bra doesn't cause this problem despite being snug and I am guessing it's that it's so wide. Maybe a really wide band is the answer.