Marriages don't fall apart overnight; people go through a process in order to arrive at their desire to divorce. In some minority of cases, the decision to divorce is made quickly, perhaps as the result of an affair, or an instance of abuse. More often, however, people contemplating divorce endure a period of ambivalence or indecision during which the pros and cons of staying or leaving the relationship are considered.
The process of being unsure as to whether to leave or stay in a marriage does not necessarily follow certain steps or patterns, and there is no set timetable for how long it will last. In fact, ambivalence towards marriage can last indefinitely. Spouses with conflicting goals or values might initially think about divorce only to later back away from that idea and attempt to make a compromise work so as to keep the relationship going. If compromise proves workable and successful and both spouses feel good about it, the marriage peace can last. Alternatively, if attempts at compromise would lead one or the other partner to compromise too much of what is precious to them, then conflict will surely emerge again. Ambivalence indicates a problem in the marriage and is a good indication that marital counseling is in order but it does not necessarily indicate whether that problem can be overcome or not.
Core value conflicts between partners may develop over time as partners mature, or they may have been present in hidden form from the beginning of the relationship. Mismatched values and beliefs can become an unmanageable problem for married partners; There are things that partners can compromise on and things they can't give in on without compromising themselves. When partners are unable to arrive at an acceptable mutual compromise, they must either split or figure out how to feel okay in spite of not being able to get what they want. As neither of these 'solutions' are enjoyable, it is fairly common that people retreat from them psychologically and remain unsure instead.
People often experience ambivalence as a pressing problem that they cannot solve, and as a painful sense of stuckness. While there are all too many cases where ambivalence ends up being a negative experience from which people have difficulty leaving, ambivalence can sometimes be a good thing as well. This indecision might be all that keeps one partner from quickly separating from his or her spouse and ending a perfectly good relationship when he or she is under the influence of an infatuating affair. The laws governing divorce in most states seem geared to support this type of 'take-your-time' path when they require a period of time to pass between when a couple files for divorce and when that divorce is granted. Sometimes the impulse to flee a relationship is necessary, and sometimes it isn't. In its positive aspect, being unsure slows down the decision making process so that better decisions can be reached.