Get a new agent; the one you have lied to you, or is incredibly uninformed about airline procedures, terms and conditions. How dare I? Easily!

Read AA's http://www.aa.com/content/customerService/customerCommitment/conditionsOfCarriage.jhtml]Conditions of Carriage, particularly where it say s"Ticket Validity," including:

"American specifically prohibits the practices commonly known as:

Back to Back Ticketing: The combination of two or more roundtrip excursion fares end to end for the purpose of circumventing minimum stay requirements.

Throwaway Ticketing: The usage of roundtrip excursion fare for one-way travel, and

Hidden City/Point Beyond Ticketing: Purchase of a fare from a point before the passenger's actual origin or to a point beyond the passenger's actual destination.

Where a ticket is invalidated as the result of the passenger's non-compliance with any term or condition of sale, American has the right in its sole discretion to:

Cancel any remaining portion of the passenger's itinerary,
Confiscate unused flight coupons,
Refuse to board the passenger or check the passenger's luggage, or
Assess the passenger for the reasonable remaining value of the ticket, which shall be no less than the difference between the fare actually paid and the lowest fare applicable to the passenger's actual itinerary"

Have a good walk.