Someone explain this injustice on modern society.?

Why do beautiful smart funny girls never get the guy? Let me explain.she always seems to get these crushes on unattractive guys who aren't right for her. My other friend really likes her and i know she'd like him back if she didn't sell herself short so much. she doesn't believe me when i tell her she's amazing because her mother has forced into her head that she's not. every one but me has abandoned her and now it really must just seem to her that everyone hates her. how do i get her to see how great she is? it breaks my heart it's like watching the princess live a pauper and nobody notices it's her.