no offense, but I think it was pretty obvious, particularly because there's no ending credits and it says "FIN?" (with a question mark) when you beat the game the first time.
Anyway, the true ending is worth it for the credit roll music and the chilling final closing scene. Just keep in mind that you have to beat the game in NG+ (increased difficulty) in order to see it. (or you can just look it up on Youtube, lol) --- Authority must be obeyed, or it must be overthrown! --- Red Queen Alice: Madness Returns