Until this season, Sam has been Frodo and Dean has been Samwise. It would be *lovely* to see those roles reversed--though I wouldn't object to also seeing Dean's "plain hobbit sense" asserting itself to help him fight off the influence of the Ring Mark/Blade. But yes, however he is saved, Sam will most assuredly have to play a role, because Dean's going down this path because he thinks Sam doesn't love him and Sam's going to have to prove by his actions that that isn't true.
Plus, the whole reason Samwise got to follow Frodo into the West was that he'd been a Ringbearer himself. So maybe this is the trial Dean has to pass through to ensure that wherever he and Sam end up at the end of the series--preferably with "There'll be peace when you are done" fulfilled"--they'll be together.