Breaking

I'm so upset and frustrated!!! I'm very close to cutting off all of my hair. I've been getting my hair colored a red/brown color with highlights about 3 times a year at the most. I used to take vitamins that had Biotin in the supplements and my hair grew very long. However, I discontinued the vitamins because they had herbs and caffeine in them which created problems. Anyway, my hair started breaking and I have lost 5 inches of length. It's shorter than it's ever been and the ends are friggin fried. I hate cutting it because it’s already short as hell. I went to the doctor and he said to take more vitamin D as I was deficient. Then, I started Biotin supplements a month ago, have used oil treatments, leave in conditioners and my hair just won't grow past a certain point. Plus, I have breakage on the top layer of hair. I’ve read not to style my hair and that’s a joke. I can’t go to my office with my hair in a ponytail, I have to use a blow dryer or it dries looking awful so these suggestions are not an option. I need realistic answers to my breakage issue. I look at old pictures and wonder what the hell happened to my beautiful, long hair!! What in the world is going on???