Look around your room. How many of your clothes do you wear regularly? How many would you say you would never wear again (despite the fact that they would fit you)? What kind of clothes do you tend to buy that you very rarely wear? How many items of clothing - do an estimate if you're not sure - would you say you would never wear more than ten or so times in your life?
Just curious. Maybe I just happen to know all the girls that have 'a problem' with shopping, but it seems 90% of the girls I get to know well end up having an insane wardrobe, often overflowing, and very often with a load of stuff they have openly admitted they'll never wear (again).