Does this make my butt look young?

My biggest pet peeve lately is wardrobe. Besides the fact that I work so much the only clothes that usually end up getting cleaned is my work uniform, I am struggling with this new situation I am encountering. That situation is being old enough to look ridiculous in young clothes while still being young enough to look ridiculous in old clothes. When I go shopping, which, fortunately, is not often, I find one of 3 things. Clothes that look really good on 18-22 year olds, clothes that look really good on the 30something mother of young children and clothes that look really good on my mother. I am exempt from all categories, but I find that the pair of pants I try on are too low, too skin tight, too Martha's Vineyard capri-ish, or contain too much elastic. There is no category for the young, no longer looking, but still want to be attractive woman. A plus for me is that I look younger than my 29 years so, to others, I don't look outlandish in 18-22 clothes, but I feel ridiculous. However, if I wear the 30something mother clothes, or my mother's clothes, I look ridiculous, because I look younger than my 29 years. Someone needs to do something. There needs to be a line of clothes for young, married, un-childrened women who want to be fashionable, not faddish, while still looking the part. I mean, if I wore the shirts and pants that my face dictates, my husband would wonder if I am actually looking to replace him. But I can't stand the dumpy looking clothes that is next in line for me. (No offense to the women who actually do look good in these clothes. It's just not me).

Is there help? Will someone show me the way? That is, if there's not much shopping involved.