I feel for you,nothing worse then working into your house to find a bright blue sofa you just bought only to remember that you do like blue and already have to sofa's.
Think we have all been there.
After 10 years of BP,the only way i manage is i don't have a credit card (refuse to get one,cut it up) if you don't have one you cant spend as much,if you have one every time you pay some money of it call the company and ask to lower the credit amount to the amount it is at until it is paid.
Now when i know i need to shop ( it feel like a need ) i try and focus and tell myself that i will buy what i need and it still give me a high.The other day a bought new presciption glass,they were not cheap but i had the money saved and when i came down i felt ok about it as i new i need a new pair ( my old one's were 4 years old ) . So when you feel ok sit and write a list of things you need...like it could be something silly like a dust pan ...any thing you can think off...and put it in your purse and keep telling yourself next time i need to shop i will get what is on the list.if you don't need anything put silly things like i need a $2 ashtray (even though you don't smoke :) you will be so focused when mania hits to shop and you brain will keep seeing the $2 part...Because it will not matter if you spend $5,000 or $1 the buzz is the same and it mets your need, but mostly it won't put you in extreme debt.If all that fails then i head for the supermarket,i get the same high from buying food as i do clothes,stereo's or sofa's except i then have something usefull to show for it ........plus it fill me up for (months)...
Generally I find it best to control spending to a checking account if possible as people can sometimes not be aware of credit card debts that accumulate over time. I believe some standard websites offer a password that you can enter that you can use to block yourself from ordering anything more if you have a joint account. I also use standard programs to enter all bank transactions such as Quicken so I can keep track of spending on a regular basis.