If you have been together for a long time, then you will recognize that there are certain signs which indicate that the partner is not as comfortable in the relationship that they could be. Sometimes they will blame the other partner for having changed their lives in too many ways, sometimes it can just be a mid-life crisis that makes one person look at the other in a different way.
The saying that people who divorce are not the same people who marry is often true, but that could also be a good thing; many people walk carelessly into a union not considering the real effects that it will have on their life, and so they enter the marriage with the thought that they might be able to change the other person or change sufficiently themselves to make it work. One or the other may notice this somewhere down the line and they don't have to wait until the other to declare €I want a divorce€ for it to be known. This is where the person might want to just consult with a lawyer, to be prepared even if they will take all the necessary measures to avoid this stage.
A divorce settlement tries to make sure that the distribution of assets is fair to both parties. There will be all sorts of issues that one or the other or both might have never considered. If the children are to go to one side, will the other side be reliable for alimony payments to make sure that a good care is maintained and that both parents retain responsibility for the continued development of their children.
Property will be an issue, especially if there has only been one signatory to the mortgage, the automobile or other assets which may have to be halved to be duplicated. This might mean selling the house, even though both of you want to retain it. One divorce mistake that a divorcing partner can make is leaving the household to establish residence somewhere else; if this can be avoided it should, because it might indicate to the opposing attorney and the Court that that person can do without the house because they were already available to find suitable housing. But that's not a firm rule and a good judge might know the difference.