Jordan St. Francis wrote:because αὐτὴ is nominative here, it must either mean "self" or "very". I do not, however, see anything in the sentence which this is predicates or is attributive towards...
Aah, you do see it, and you've even translated it correctly, but most of us aren't used to thinking about agreement this way. αὐτή here is agreeing with the implicit subject, marked in the verb ἔχεις — "you." So, "you yourself" or the like.
Here's another, somewhat grandiose one — αὐτὸς ἥκω, "I myself have arrived."
This sort of agreement with a subject that isn't expressed except by verbal morphology is fairly common. If you have a nominative adjective with no obvious noun to go with it, look to the verb. This sort of construction also sometimes occurs in accusative + infinitive
clauses, where it can be genuinely puzzling. Here's a little Anacreontic ditty — note especially the last line:
χαλεπὸν τὸ μὴ φιλῆσαι, it is hard to not love
χαλεπὸν δὲ καὶ φιλῆσαι, and it is also hard to love
χαλεπώτατον δὲ πάντων, but hardest of all
ἀποτυγχάνειν φιλοῦντα. is loving, [then] to lose
So, with χαλεπόν it is difficult (to)
one uses an infinitive construction. In the last line, we have φιλοῦντα, a present participle in the masculine accusative
, but not a noun in sight with which the word could agree. So, we need to take it as agreeing with the subject of the verb ἀποτυγχάνειν, which is never actually expressed, but implied by the infinitive construction.