先阅读短文，然后用下面方框中所给的单词或短语填空，使全文在逻辑上正确。

upset/ thought/did wrong/found out/ else/other

Dear Mary,
I have a problem, and I need your help. I always    I was popular at school. But I just    that my friends were planning a birthday party for my best friend, and they don’t invite me. Everyone   in my class was invited except me, and I don’t know why. I can’t think what I    . I am very      and don’t know what to do. What do you think? Can you help me?
Yours
Lonely Kid.