Hello, manxcatwoman. I did some looking and found two articles that may be of benefit:

Crying Spells
Common causes of Sudden onset of crying spells - RightDiagnosis.com

Sorry you have to deal with the spells. Perhaps, your general practitioner may have some answers for you? Or, see Clyde's answer here: http://answers.psychcentral.com/Gene...for-no-reason/

I wish you well.