Peter Pan ending

In my opinion, the ending of Peter Pan is half happy and half bad ending. Because in the ending Peter Pan they overcome the Captain Hook and killed him by crocodile. This part made me feel that is a happy ending. However, Peter Pan must leave Wendy, in order to not be catch and become a man. But Peter Pan promise he will see Wendy once a year. That's the reason why I feel sad in the end. Because of these things made I feel the ending of Peter Pan is half and half.