my guess (based on having no medical training) is that long-term use of klonopin leads to dependence and therefore withdrawal when suddenly stopping use. i imagine that's why your previous doctor told you not to stop taking it -- although i find it hard to believe that he/she said to "never" stop just because you had been taking it for awhile. you could of course ween yourself off it to avoid the withdrawal symptoms.

in any case, it seems you're not in a position to ween yourself off, so as the others have recommended, you should find a new doctor, who could at least prescribe or give you some on a compassionate basis until things get sorted out. also, why not call your old doctor and explain the situation? he/she should be able to help you handle this short-term problem, too.