wear thin
     v : deteriorate through use or stress; "the constant friction
         wore out the cloth" syn: wear, wear off, wear out
see also:
wear wear off wear out 

34 moby thesaurus words for "wear thin":
   bomb, break, cave in, collapse, come apart, come unstuck, conk out,
   crumble, decline, disintegrate, droop, drop, fade, fail, faint,
   fall flat, fizzle out, flag, give out, give way, go downhill,
   go soft, go to pieces, hit the skids, languish, peg out, peter out,
   pine, poop out, sink, weaken, wear away, wilt, yield