Regret theory?

Have you ever feel that you brought a thing and you feel regret~
It happen on me all the time~
It is because sometime I saw something and I feel like it is so nice, suit me and....
But when I bought it home, then I will start regret, I will feel like " how can I bought this UGLY thing? I does not suit me at all.

 How the dress look before I bought it~

How it look after I bought it~

 How contradictory am I? 
Actually it is called Attitude Change Theory~( What lecturer told me)
Actually this happen on me because of Cognition...
Sometime I feel like I need this dress so much for me to go party or ...
But When I bought it home, then I will feel like I have the alike dress at home or that dress not suit me to go anywhere~ I waste a lot of money, And I need to cut the budget that I used to eat~(CRY)
I have many useless stuff at my room, it made me look sloppy and always get scolded by my mom~
How should I clean this thing away???????