Love comes first, then comes marriage, then comes decades of time together strewn with a minefield of potential relationship wreckers. Here’s how to have a healthy relationship every step of the way:

1. WATCH YOUR WAISTLINE

Now that you’re married, you can finally relax and skip the gym, right? Wrong. Wedded couples tend to have fatter waistlines, which can spell trouble in terms of sexual attraction and general health. So unless you want “till death do us part” to include chronic health issues like heart disease and diabetes, it’s important to establish healthy eating habits early on.

2. HAVE A FINANCIAL PLAN

Nearly 40% of married people admit to lying to their spouse about a purchase, according to a 2004 poll, and money woes can quickly send your marriage south. In fact, money is the number-one reason couples fight and relationships tend to suffer during poor economies. You should discuss and agree upon some hard financial ground rules, preferably before you tie the knot.

Don’t fret if you’re a spendthrift and your partner pinches pennies. You don’t have to have the exact same philosophy about money; however, financial issues are best to resolve early on. You want to decide who is going to pay the bills, how much discretionary spending is reasonable and how you’re going to keep track of it all.

3.  FIGURE OUT YOUR FAMILY RULES

People often don’t realize that they come into a marriage with an idea of how a family works based on their own family—whether they got along or not. You can end up fighting over trivial things but those issues can add up to big problems, particularly if children enter the picture.

You and your partner may have vastly different ideas about how a child should be cared for and what constitutes family together time. If one of you is working, should the other partner get up with the baby at night, or should you take turns? Is it important for you to sit down to dinner as a family every night? You need to figure out how you can live together happily while each maintaining your own sense of self.

4. MAKE SEX A PRIORITY—BUT NOT A CHORE

While you should make sex a priority, you shouldn’t pencil it in on your planner. If you schedule sex, it becomes a responsibility. The average married couple has sex 58 times per year, or slightly more than once a week. And a recent eight-year study found that 90% of couples experienced a decrease in marital satisfaction after the birth of their first child. But it doesn’t matter whether you’re having sex five times a week or five times a year—as long as both of you are happy.

5.  BE FLEXIBLE

Whatever financial and household arrangements you agreed to in your 20s or 30s, chances are they’re going to change at some point in your marriage, meaning couples are making some hard choices when it comes to both their careers and their checking accounts.

If the traditional breadwinner is laid off, the stay-at-home parent may need to head back into the workforce. Conversely, if you become a stay-at-home partner—due to choice or circumstance—expect to do more of the shopping, cleaning and other chores that make a household run smoothly. Having an open discussion of how household duties need to change can help couples weather some tough transitions.

6. STAY ACTIVE AS YOU AGE

Pick up a life sport that you can enjoy together for decades to come, like golf, tennis or hiking. You don’t need to be seriously sweating to reap the benefits of regular exercise. Experts say that moderate exercise is enough to help stave off heart disease and other ailments.

By Mauricio Portillo