There are a number of problems in a relationship that can be considered as marriage breaking issues. Jealousy is one of them.
Most of the time the source of this terrible feeling can be traced back many years. It is caused by a bad experience in early years and then it has become part of the personality. So unless there is clear evidence that the spouse was or is unfaithful, this jealousy is not caused by what happened in the present but the underlying jealousy is rather triggered by what is recently said or done. A jealous person is a wounded person and what you see is the result or symptoms of that trauma.
Jealousy is often hidden or partly disguised before marriage. Even when at that stage we get a glimpse of this unjustified behavior, we tend to rationalize it and seek a reason why it is allowed and don’t object strong enough. So we "tie the knot", not realizing we have just tied and restricted the freedom to be ourselves.
If not treated, jealousy will become worse for no-one can escape the constant and many and unavoidable triggers that light up that bad tree inside of us. Furthermore jealousy is directly connected to sexual energy. That means everything that is perceived as sexual has the immediate effect of an energy rush and is very difficult to ignore. So instead of feeling love, we feel jealous.
People overcome by jealousy become nasty and impossible to live with. Tragically they always project guilt unto others as if they are the reason for what they feel. Their default position is to not take responsibility for their own feelings. When the goalposts are constantly shifted it leaves the spouse with a no option solution. We have to understand that a jealous person cannot ever be pleased by what the spouse does. It’s like trying to fix a car by working on a car parked next door.
The solution lies inward not outward. Probing into this feeling, you will probably find one of three foundation feelings on which all negative feelings are stacked, namely guilt, shame or fear. My guess is, you’ll end up dealing with fear and the false beliefs that has been set to escape the fear and stored on a survival level of how to best deal with this.
Jealousy and nastiness is a choice but only for those who understand what they have just read.