Correct. You made the decision to buy non-refundable tickets that clearly had a validity period. AA didn't make that call. Then, AA already did you (and all of us) a favor by extending the validity period multiple times. You made the call not to take advantage of that. All of this is and was your call, not theirs. If you wanted the additional flexibility, you had the choice to buy refundable tickets. You instead bought non-refundable tickets, which cost less but come with various restrictions, one of which is a validity period.

In the original post, you said you lost track of the tickets and seemingly forgot about them. AA isn't responsible for how each of us manages our credits with them. For example, I treat these like "cash" and enter them in Quicken for tracking purposes.

I'm sorry if this sounds a bit harsh, but I really don't think AA has any fault here. As I said, AA does some dumb and irritating things -- this isn't one of them.