How can i help my friend?

she is in deep love with someone wayy out of her reach. he's the most popular guy in school and has had many girlfriends & knows soo many people. but shes the oposite. they talk every so often and get along ok, but in high school pairing up like that just doesn't happen. she tells me about how she cries herself to sleep because she knows she can never have him. Wat can i say & do to comfort her?? i try to tell her its possible to ge twith him, but i honestly doubt it is. but i don't know if she wants to get her mind of of him, wants me to dream of him with her, or wants me to joke about it. & i don't wanna ask her bcuz thats weird & might make her even more sad. i feel bad when i her her obsessions when i tell her i got a cute pic of him or when i hear her telling me tha she cries herself to sleep bcuz she's without him. idk!!! how can i hel pmy bff???