Why do girls cry over celebrities ?

My cousin is obsessed with this boy band Hanoi Rocks they're a band from Finland I never heard of them until she started talking about them they don't sound to bad. She has a crush and a huge obsession with the bass player Sami also the drummer Razzle she's upset that she'll never get to see them because the drummer died they're not together anymore she said him and lead singer Michael still tour together only in Finland and UK and places like that. She said Sami just came out with a new song and is releasing a new album he said he maybe doing live shows hopefully he comes here I'm afraid she's gonna hurt herself if she doesn't see him. She said it's not fair his wife is around her age he's almost 60 it makes her think she's not beautiful it makes her sad and depressed. When she's sad or having a rough day she wishes she can talk to him on Instagram but she's scared she's not good with talking to celebrities also she's afraid she might say something to hurt him or say something stupid. She's so in love with him she worships him. She has a fan page for them on Instagram she does a roleplay with her friend where they pretend to be themselves and the band members and pretend they're married to them she does it all day long. When she sees pictures of him with wife or when he was younger it makes her cry. She calls him her baby or her boyfriend. Why do girls cry over celebrities ? How can I make her feel better ?