I vote to buy a new bike and keep the old one for the really crappy days and keep your eye out for another good used one to replace it. I assume that the threads on the BB are what are stripped? If so there are several solutions, some inexpensive and some not. Loctite Red is the down and dirty cheap fix. Phil Wood (IIRC) makes a bottom bracket replacement that will work when there are no threads to work with. It might be possible to tap it out a bit over sized and mount a different brand of BB (those are the more expensive choices)

Aaron