Oddly enough that may SEEM like a gaping plot hole. She appears not to hold a job as such a professional. She is a staff member to help the mentally disabled.
If you watch the movie's beginning during when Stiller is wondering about Diaz he gets a whole LOT of conflicting ideas about what "Mary" has either become or is doing. The truth is only revealed when we meet Mary in Miami.
It's not a ruse. Stiller's chiropractic knew a different "Mary" which was not Stiller's in Las Vegas. Oddly enough, in all of our humanity, maybe you know a Mary as well and contribute a story to someone like Stiller which is not the same person Stiller's soulmate is.
Speaking of names, aside from Chris Elliot's character, does anyoine know the last names of the other characters?
--SG2H
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