There are few exceptions when the Church allows the separation of spouses.
“Which are the cases when the Orthodox Church allows the divorce?”
“According to the teaching that we have received, marriage is indissoluble, meaning for life. ‘What therefore God hath joined together, let not man put asunder’ (Matthew 19:6). Death alone may separate the two spouses”.
However, there are some ex when the Church allows the separation of spouses by divorce. Divorce is the legal dissolution of marriage, for which the Church cannot give them any blessing or juridical decision. This is the reason why people do not need any service from the church when they get a divorce. The only legitimate marriage is the first one. Its legal dissolution interferes when one or both of the spouses die, for after they die, they are like angels, unmarried (Matthew 22:30).
“Even so, the ecclesiastic leaders, bearing in mind the moral purpose of marriage, since the Apostle’s time, have allowed for widows to marry again. Thus, as an economy between the two alternatives: of a superior widow, in full abstinence (Luke 2: 36-37) and that of debauchery, they have allowed for the second marriage” (1 Corinthians 8-9; 1 Timothy 5, 3, 6, 14), as it is written in Pravila Bisericească, the monumental work of Nicodim Sachelarie.
(Translation from Arhimandritul Cleopa Ilie, Ne vorbește Părintele Cleopa, ediția a II-a, volumul V, Editura Mănăstirea Sihăstria, Vânători-Neamț, 2004, pp. 17-18)