It is not a role; it is not even an alter ego. In the film The Wrestler, professional wrestler Robin Ramzinski's in-the-ring persona, Randy "The Ram" Robinson, is real. It's who he is."The Ram" fights larger-than-life villains, endures incredible punishment, and absorbs the adulation of fans. His life is high drama. But the needs and ego of such a character render the man outside the ring dysfunctional. He can't sustain a relationship or a job because each demands that he recognize the needs of others and endure punishments that are less physical and bloody but real nevertheless--and often less dignified.
And as the times change and his original fans move on, the limbo known as life between matches gets longer and harder. By the time the film begins, Randy is already nearly invisible, sleeping in a van in a trailer park, far out from under the lights of the ring. By contrast we see Randy's fictional former arch enemy "The Sheik", who now runs a successful car dealership. When he returns for a reunion match, "The Sheik" is thinking business because that's his life now.
We don't know why or how Robin became Randy so completely. The Wrestler just gives us a biographical glimpse of professional wrestler Robin Ramzinski in the twilight of his career. But as far as Randy "The Ram" is concerned, this is simply the end.
