The Cause of Overspending

Ample market research shows that people who overspend usually do it to feel good or to feel in control, not because they need the items they buy. Slapping down the plastic makes them feel powerful, secure, able to make their way in the world. 

So chiding your spouse, or even just stressing the virtues of scrimping and saving, is going to backfire. The more you talk about that stuff, the more your spouse will feel out of control - the same emotion that drives the indulgences in the first place. 

A more effective strategy is to encourage your spouse to own the problem. Keep track of what your household spends, weekly or monthly, and ask him or her to review those accounts. Don't say anything else. That way the choice to cut back is under your spouse's control, making it more likely to happen. 

If that doesn't work? You know the time has come to get separate bank accounts. 

Finally, you might consider lightening up a little. Marriage is one of life's great blessings. If you think the occasional iToy is expensive, wait until you see how much a divorce costs.  

Tyler Cowen in Money Magazine