The problem of personal identity is often found in good drama.
It’s an excellent theme to play with. Who does the hero think they are? Why can’t they see who they really are? What’s their Achilles heel?
Making them unsure of who they are is a good (albeit unsteady) first step towards their transformation. Or lack thereof if the drama is to be a tragedy.
Seeding elements of the antagonist into the identity of the protagonist is a fine way to internalize the drama, to embody the friction.
Pitting the hero against themselves is a fine way to incorporate the drama.
Put their plight in their own hands.