<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Here is an outside shot at getting them back. Can you find a hotel or car rental activity someplace that would have kept you going for another few years? Try to get manual credit which would reactivate the account.</font>
That route will work. My husband had some miles expire last year. Same story, they never processed a change of address and he had not been getting statements. I found a hotel stay that had not properly credited to another airline and submitted it to Delta. It took them months to research and post the hotel miles but when they posted the expired miles were put back in the account.