Need advice!!!?

My mother and I started a plus size womens clothing store in a small to medium sized town in Kansas. Its on Main st where lots of other retail businesses are. And tho we cater the clothes to plus size women we carry name brand purses, nice jewelry and scarfs and hats and gloves. And we carry sandals in the summer! lots of things other than plus size clothes. we thought it was a great idea because the only place in our town where you can buy plus size is walmart! Our prices are moderate, we dont even mark things up to there retail value! The first year was ok(it kept the bills paid) the second not so hot! and now we are dreading starting the third year! Please help this is my mothers life long dream! i dont want it to fail! We spend around 25% of our monthly income on adverising..we advertise with three newspapers...two radio stations and send out newsletters! and its still not bringing in the customers!Our target age group is 18-60 we carry every thing for every women thats why my mother and i started the business together...im 20 and shes 42 so we get a wide range of style difference from out age! And i dont think our clothes are frumpy i think we sell very nice things and we are small town so we wouldnt sell a thing that we wouldnt wear ourselves or that is damaged! Our customers that do come in are always saying what a great store we have and we have so many cute things but yet they dont buy!