The "medical world" does agree that there IS people who want sex obsessively so that it fits to criteria of neurotic or obsessive behaviours. It's listed as one of the symptoms in many mental ilnesses or conditions. Former maniac depressive aka bipolar disorder or obsessive-compulsive disorders etc.
http://www.sexhelp.com/depression.cfm
Now we are really far from what the orginal writer of this thread wanted to hear. But there exists a kind of sex addiction(s) that can be called nymphomania or then call it something else, but it can get you to go to a shrink instead of bed with someone.