Does this happen to you? You walk into a store and you see "it"....whatever "it" is that calls to you, "it" could be a purse or a pair of shoes or a bracelet or the latest electronic toy, it doesn't matter, you are in love and you must have it!
Try to think about it like this: I didn't know it existed 5 minutes ago and I was relatively happy, can I walk out of this store and pretend that I never saw it? I know it will be possible for me to live a full life without it because I was doing that before I even saw it!
If you just walk away chances are you will have forgotten about it by the time you get home. If you are still thinking about it sleep on it, usually after a night's sleep you have a better perspective and you decide that you really can't afford it or simply you just don't need it.
Don't get me wrong, it is fun to have nice things sometimes or a new gadget to play with but that feeling will wear off after a short time and the nice thing you bought won't be new anymore and there will be some newer better version of the gadget you had to have and you will have to do it all over again to get that "high". Try to get your "high" by putting money into your emergency fund and watching it grow or putting money into your kids college fund, or by paying off those extra bills and trying to become as debt free as possible. Who knows maybe after a while you'll be addicted to saving and you won't have to fight off those impulses to buy things you don't need.