I too have been struggling with this subject for a while your help is much appreciated.

Tony

Divorce case files (1858-1937)
Search the Catalogue by name of petitioner the husband or wife who starts legal action in a divorce,
respondentthe spouse who is being divorced or co-respondent a person accused of adultery with
the spouse of the petitioner for divorce suitslegal suit - a case heard in a law court in England and
Wales, both successful and unsuccessful, in J 77.

http://www.nationalarchives.gov.uk/records/looking-for-person/divorce.htm

The survival rate of divorce case files is:

1858-1927: almost 100%
1928-1937: 80%
After 1937 : less than 0.2%

Decrees absolute (1858 to present)
Find the decree absolute a document finalising a divorce to obtain legal proof of a divorce in England or Wales by requesting a search (£There may be a charge for accessing this information. Searching indexes may be free.) of the Central Index of Decrees Absolute. To do so, download Form D440 from Her Majesty's Courts Service website http://www.hmcourts-service.gov.uk/courtfinder/forms/d440_e.pdf and post it to the Principal Registry of the Family Division.

http://www.hmcourts-service.gov.uk/infoabout/family/index.htm