The Honesty Rule

"The honesty rule states that if one should decide to enforce the honesty rule in any situation, others involved must tell the truth, the whole truth, and nothing but the truth. Of course, the honesty rule may only be used in deadly serious situations."

Kate, Harry, Chloe, Hunter, and Madeline were that group of people in their school that got along with everybody. Kate and Harry have always been the closest of the group, joined at the hip, and Harry has always been in love with Kate. Everyone knows it except her.
One night, when Harry and Kate are stuck in a gas station bathroom overnight (it's a long story), it suddenly hits Kate that she loves Harry. They start dating and they're so in love and life is perfect and no one wants the moment to ever end.
Until it does end.
In a heartbeat, Kate's life goes from perfect to really, really screwed up, and she doesn't know how to deal with it.