Problems in the Fashion Industry

I usually can't find problems with the fashion industry, but while shopping online on Forever21's website i remembered a long standing issue I've had with the fashion industry: Sizes. Not only does each store have a slightly different or completely different way of sizing (i.e. at Forever21 I'm a larger, an XL at Kohl's and a XXXL at Dot's.). I'm not a plus size girl, but some stores make me feel that way. It's not only the variations in sizing of clothes in general, but more specifically the sizing of bust areas in tops. I'm a size D when it comes to bra cup sizes and it's hard to find dresses and tops that fit me, because a lot of them have a select area for the bust, and a band below it to cinch the waist. If i were to wear tops and dresses like this my bust would be either sliced in half, make my boobs feel weird and look weird, or there'd a lot of uni-boob, or a lot of cleavage, and i don't want to look slutty or have people view me as being slutty.
This isn't just a problem with my size D boobs, I have friends who have size C cups boobs, and they are healthy,lean girls, and they have the same problem as i do. Some how the fashion industry seems to be incapable of making clothes that fit all types of girls and that's a problem. The fashion industry needs to understand that not every girl is a B cup or even a C cup or smaller, and that they should try to provide for every size, not just the smaller ones, or more common sizes. I know more and more girls who are larger than a B cup and we are increasingly finding problems when it comes to shopping. The ideal shape and size for clothes may be thin and skinny, but not all girls and women fit that mold.
I'm not saying all stores do this, but a lot do, and I still love clothes and fashion, and I'm not angry at Forever21 or anyone else, i just want designers to realize that all girls and women's needs need to be met, or at least more of our needs.
-Fate