I tend to tear my nails off... but I have heard good things about that nail polish that tastes nasty... but your concern is not foolish, really. We might have secondary issues to addiction that--to us--are probably more important than the 'underlying' issue... Bad addict.... go stand in a corner...
And of course, by definition, my nails are hard to chew off... good luck to you and I'm sorry this is the best I can suggest.
-TB
ps I have a Syphilis--yeah, from a street festival a few years ago--that's real squishy and I can throw up against the wall to relieve stress... anything can work, if you have an imagination...