"Why are you wearing that stupid man suite?" means what to you?? the quote is from frank in Donnie Darko?

great movie btw...i feel like it's referring to the fact that we all wear masks; we all act like different people sometimes, and there are many different sides to each person. the only difference between frank adn donnie was that frank's mask (suit) was tangible and outwardly visible.

I think what Frank is Telling Donnie, is that he is not being himself, and acting like a follower is stupid. He should be himself and take the façade away. Frank is the only "person" (I use quotations) that Donnie is completely open with, and Frank bears witness to all of Donnie's actions, he even makes him do things that he wouldn't normally do. I do not know why I love this Film so much, but it is Amazing, I love it and recommend it to everyone.