I think I found the cure. Find so many decks that I really, really, REALLY want that I become paralyzed with indecision and don't buy any. Oh, and of course, giving my wife all my credit cards helps.
ETA: I suggest that being "paralyzed with indecision" is better than being "paralyzed with fear." "You bought HOW many, you miserable little . . ." No, she's really a very lovely lady who spends her own small fortune on "stuff," so I at least have an arguing point. (A true addict knows all the angles