I am sorry you are going through this. I have been having this problem on and off (almost always on though) for the last 8 years. This hit me in NY second semester if college.
I may not have much to offer but I do second the Colloidal Silver for armpit bo. Just buy a really good Colloidal Silver ( not the real cheap one some people have been graying because its so cheap and bad) and put it in a 97¢ 2 oz spray bottle. Spray it on your underarms after you take shower with unscented (No Fragrance at all, if it has fragrance in the ingredients do not buy at all) soap. Since I live in a year round warm climate (Florida) I put some all natural fragrance free deodorant (Schmidt's, can be a bit pricy though) after the silver dries on my underarms. The silver works a million times better than magnesium oil and it naturally kills the bacteria under your arm.