Looks to be at the end of its life either way. Suggest troll Craigslist or local bike groups... should be able to find a used Trek, Giant, etc., for little cash (I see nice ones all the time for $50 to $75). Then sell of the salvageable parts from the old one to help offset the buy cost. If you old saddle was well broken in, suggest reuse it.

Worse case cruise to bikenashbar.com and look at their nice alloy frames (in several styles such as road, tour, cyclocross, etc.,). They are rather well made {elsewhere**, but routinely discounted to $99 plus about $40 for a new matching fork.