Chicago winter symptoms and conditions

I started taking Doxy 100 mg July 2007 for the first time. At first I didn't link my side effects to the pills but after a break from taking it and started up again I finally out two and two together. First, it upset my stomach BIG time immediately after starting on it. I felt bloated and everything I ate upset my stomach--as the result of this I lost about eight pounds from just not eating anymore. I even went to see a GI doctor about my stomach problems! Who recommended I eat more fiber and get more exercise (I told her about all the meds I was on)! I also got sudden and very severe headaches, but the worst side effect of all is the extreme mood swings I had. I think I was going crazy and this almost ended my marriage...all of a sudden I developed low self esteem, constantly thinking I was worthless, fighting with my husband over the stupidest things and even contemplating suicide during the worst spells. I couldn't figure out why the sudden change- at first I thought it was the tough Chicago winter, since I am originally from a much warmer climate, because by this time I had been on doxy for about five months.
I was prescribed the medication to help clear up moderate acne on my back and my dermatologist gave me the prescription for a year, but never said come see me in a month, two months, etc to see how you;re doing. I am so glad that I stopped taking it in February 2008 --- my moods suddenly got better, I was myself again, I started eating again, my GI problems disappeared...and then...in April I started taking it again because with summer coming up again I wanted my acne to clear up- BIG MISTAKE! Within days of starting again my stomach started being upset all the time regardless of what I ate. After the first month I was feeling depressed again, hating myself and not knowing why--this is when i finally figured it out...and decided to stop...I'd rather have pimples on my back than feel the way this medication make me feel, which is pretty much miserable!