So this is basically any classic fairytale, but with a twist.
Whatever curse that is placed on the princess, was placed on her by her best friend, per the princess' request.
Ex: Princess, age 7: "I don't wanna get married! Boys are gross! I'll turn 102 before I'll willingly get married."
Best friend, also age 7: "I can help with that" *stays up all night to perfect and place spell on princess so she will be 102 before she can get married*
Princess, age 16: "Oh prince (fill in blank here) is so wonderful! I can't wait to get married next week!"
Best friend: "Sorry, when now?"
*Long explanation on why that can't happen*
Princess: "I'm literally going to kill you. I can't believe you actually did that!!!"
Best friend: " You SAID you wanted it!!"
Princess: "I was seven!!"
*Goes to talk to royal wizard*
Royal Wizard: "I can't undo this because of (fill in blanks here), but I can do this, (almost worse than just dealing with is alternative)"
Princess: "... Fine!!!"Just a few thoughts. Really want to read this, don't wanna write it.