obsession over item purchase

I'm currently having an obsession over an item purchase

it's a cd (I won't give album or artist, that's not needed in this situation),

but my obsession is that I keep having to purchase the item- again, and again, and again.

the cd itself is £23, so to buy lots of copies when what I have all ready works seems awefully expensive

and then if it's not in a certain type of case with a certain picture on the front, it's made worse and I just have to throw it away and look for it again to rebuy it.

Find the one you want and buy a couple of them

well, that sort of works,

until I find that their's new ones of the same item up for sale and I have to have them

let me try to explain it better:

I'll use a dvd of family guy as an example:

in a shop, their are 20 copies of family guy season 7

I go in the shop, see family guy season 7 has 20 copies on the shelf, and buy them all.

I also see family guy other seasons, but don't buy them

next day I'm in the same shop, and see family guy season 7, but in a diffrent case- so I leave it alone

and then more copies come in in the case I have at home (the 20 copies I own), so, I have to buy those ones on impulse too.

this is how it works for me- so I could buy a few good quality copies, but it will never be enough