CONSUMER BEHAVIOUR

Why do we buy certain things and how come we can do so and simply be unaware that we are adding to some consumer addiction.
Its still raining by the way so am focussed on the inside of the house for the moment. I am glad it is raining as the garden really needs it and can turn my hand to my summer and winter clothing. I felt an urge to go and get the colourful summer things out and take a stock of what is actually in my wardrobe. I have managed to fill a complete bin bag with clothing to go to the charity shop; items such as coats that moved with us here 3 years ago and have been hanging in a closet, as well as a suit my husband has not worn for 15 years. I could hang onto it if it was of a certain quality but even that is dubious.
What I gathered from the clearing up is that I have a fetish of black trousers. I have 10 in my collection. How many can I wear at a given time, 1 actually. So I have made a little note in my diary about things not to buy, such as black trousers, coats and black and blue skirts as again, I have a large collection of those in any possible black you can imagine. ( There is only 1 black colour actually). The styles are a little different but they are basically still the same item. When my friend emptied her wardrobe and I had a portion of it, yes you guessed it, I went for the black trousers bringing home another 3 pairs.
How many items does one need in a working wardrobe? Anyone any suggestions as if I could just create a capsule wardrobe that suited me and that was flexible, I might only need a few items each season if I wanted to have something in the fashion colour of the day. That in itself is debatable at the moment.
Do any of you have a list of clothes?