If Isabella Swan had just one close friend from Arizona, I don't think she'd want to turn into a vampire. If she had one actual, true best friend from years and years of ballet and surviving middle school together, and crying over boys together, and laughing and the crazy stuff Rene did together, she wouldn't give her up for immortality. She could not.
Think about how different Twilight would be if Bella wasn't written as a "not like other girls" friendless weirdo. Like, yes, obviously Smeyer wanted her to be strange because ultimately she was "meant to be a vampire" but the impact of a single best friend would change everything in the entire series. Having someone to actually keep a secret from would destroy Bella. She couldn't hide something that major from the person she had a Weirdo Bloodpact with. She couldn't tell her best friend something that would endanger her either.
Idk. Making Bella friendless was probably the cruelest thing Smeyer ever did to her. Even her Forks friends are incredibly shallow and impersonal friends. Angela wanted to be closer to Bella, but she wasn't sure how and Bella made it hard.
James finding best friend rather than making a fake out tape...