OP, worst case you need a new crank set, not a new bike. The affected parts can be replaced. Often the affected threads can be salvaged by cleaning and straightening them with a tap. A GOOD local bike shop (LBS in forum parlance) can do this for you. Beyond that there are other solutions still short of replacement of the crank. This happens all the time and a good shop should be familiar with the problem. See your LBS, but try to pick a very competent one.