It can be very hard to understand why your partner would lie to you. After all, if you’re married you each took vows to love, honor and trust one another.So how do you deal with a partner who doesn’t tell the truth? “Lying can feel like a serious form of betrayal [but] if you catch your spouse in a lie, it is important to examine your reaction [since] your behavior may influence the likelihood that your spouse may lie again,” writes Amy Morin, MSW, who offers advice on her marriage counseling blog. Changing any kind of behavior – including feeling suspicious of a spouse – takes time. And his changes in behavior will also take time. So give each other some room, talk about things more often and more honestly. In most cases, a relationship will begin to improve over time, though in some cases one or both partners may also conclude that the damage done by lying cannot be repaired.