This will only make sense if you've watched Gundam. Emo time 0:30 onwards.

link

Basically, Amuro Ray, the pilot, is preparing for battle with his arch-rival. He's now 29, and his rivalry began when he was 15. At first the girl wishing him luck is Fraw Bow, his childhood friend and loyal supporter throughout the original series, and the view flickers to the woman that he's seeing in the "present." Basically, the memory of the past supercedes the reality of the present. Throughout the rest of the clip, Amuro fights Char as he changes mobile suits until finally both Char and Amuro are using their newest rides.

The nostalgia... it hurts.