What was miley cyrus's inspiration for 7 things?

Miley Cyrus wrote 7 things for Nick Jonas. 1.She says "your insecure" Nick is known to be shy. 2.Jonas brothers Burnin' Up video came out before 7 things. Miley says "you like me, you like her" In Burnin' Up Selena Gomez is Nick's girlfriend 3.She says "your friends are jerks when you act like them just know it hurts" Could Miley be talking about Joe and Kevin? We don't know how they really are. 4. She says " I want to be with the one I know" Everyone knows she started out saying she liked Nick. 5. Miley says "the 7 things I like about you, your hair" Everyone loves his hair! 6.She says " your eyes" Everyone loves his beautiful eyes. 7. When Miley holds up a picture of both of them but has a white mark over the face, you can tell it's Nick by his hair and face structures. 8. At the beginning she kisses the dog tag Nick gave her.