According to John Hoag, who specializes in Spousal Abandonment therapy:
Spousal abandonment occurs when a marriage breakup is initiated by one partner (the leaver) suddenly, without just cause, and without warning as perceived by the other partner (the leavee). Often these marriages are long term (10 or more years) and have every outward appearance of having a long and happy future ahead of them.
Before the breakup, the leavee together with friends and family may consider the marriage to be generally normal and perhaps even exceptionally happy. Such breakups are also known as “sudden endings.” Unfortunately they are becoming more and more common for reasons sociologists are not yet able to explain.
Since marriage involves multiple dimensions — identity, trust, family, spirituality, community and law in addition to expectations about the future, dreams, planning and investments both emotional and financial — suddenly abandoned spouses sometimes describe their loss as being even more painful than the death of a loved one.
Sudden abandonment without just cause involves a leaver’s deceit, betrayal, the breaking of solemn vows, a lack of concern for the welfare of the leavee, and most frequently a lack of remorse.
Abandoned spouses grieve deeply and experience a range of emotions including anger, loss of trust, fear, anxiety and depression over long periods of time. The timeline for “leavees” to heal from sudden endings is typically longer than that for mutual breakups, and many times longer than the readjustment time needed by “leavers.”