1998 Subaru Forester - busted head gasket

Thank you for your replies! To answer a couple of questions:ok4450 - yes to everything. Except it only overheads when driven, not when they run the engine in the shop (why they didn’t catch it before, they tell me). But it would overheat in my 3 mile commute to work. I’m planning to take it elsewhere for a second opinion - I’ve been checking around and apparently there is a superb shop for japanese cars close by - wasp automotive anyone?
I’m realizing I need to have this fixed, whether I keep or sell the car. However, I don’t want to keep an unreliable car anymore than I want to buy a new one. I’m worried about other parts failing due to the increased pressure of a new seal - is there precedent for this after a head gasket repair?