Looking from the outside in, you'd probably think that when marriages and other long-term relationships go bad, it's usually due to marrying too young, infidelity, maybe getting fat. You know, all those things people think about in relation to love and sex. But what people in these relationships quickly realize is that the real threat is often money. More specifically, where the money goes that the two people in the couple bring into the home.

Author and financial advisor bambi Holzer's new book Financial Bliss tackles both the psychology of merging (or not) your finances, as well as the nuts and bolts numbers game in terms of where you should be concentrating your cash. Her financial advice on mortgages, insurance, retirement, etc. isn't anything you couldn't find elsewhere---it's the time spent on getting couples on the same page that makes the book worthwhile.

Think about how little couples often know about each other's money style going in, and you'll realize all the things that need to be discussed. What things do you and your partner consider important to spend money on? Maybe he thinks the latest vehicle is a must while you want to save for a house, or vice versa. Maybe he thinks you waste money on too many clothes, while you think he doesn't need the latest cell phone every other month, or vice versa. Maybe he wants to put your money in high-risk investments in a bid to get rich today, while you want to hit the 401(k) and index funds, getting rich via the tortoise route. Or vice versa.

The point is, a relationship that started with love words and gifts under the pillow can end up in hate words and accusations of treason if you don't work to understand each other and then come up with a plan to make it work. Holzer says that plan is different for every couple. Maybe you pool your money and each side does some compromising, maybe you keep the majority of your finances separate so no one can get angry about the other's spending.

To get to a point of understanding, Holzer offers a number of exercises that will help partners understand each other's money styles, including saving versus spending habits, risk tolerance and more. She then prods you to talk, starting with a financial State of the Union meeting in which you pull out all the paperwork. Calculate your net worth, see just where the monthly money is going, then come up with some mutually agreeable goals. Then you get into the nitty-gritty financial details like insurance, retirement savings---all the stuff you really would rather not deal with.

Financial Bliss is a book for both partners to read and work with, and in that way it can be a fun way to learn more about each other. My wife and I could do better in this area and I'm going to suggest we sit down with this book just as soon as I get back from the racetrack. (Don't tell her where I am.)