I heard some information was leaked the night before. Because numerous fans found said information upsetting, this post thing was taken down. I am about to tell you this, the ending to Thank You and Goodbye.
SPOILER ALERT[]
Amy will break it off with Ricky and choose Ben. After telling Ben that she's his, he goes for a drive. Since he is so happy, he's not paying attention. A drunk driver will crash into his car and will kill him. The last scene is supposedly the paramedics pulling a sheet over his face, thus ending The Secret Life of the American Teenager as we know it.