meaning - What does 儚い mean in this context?

I want to translate this twitter status of AKB48 member. She wrote about the graduation(retirement) of one of the member, but I'm not sure what 儚い mean in this context.

According to Jisho, it can mean

1. fleeting; transient; short-lived; momentary; ephemeral; fickle; vain


2. empty (dream, etc.); mere (hope); faint (possibility)​

I was wondering what does she mean here?

EDIT: I'm currently confused between

1. 
   

   Mayu's beauty is fragile and delicate (cause she does have that pure idol image)

   
   

   or

   
   


2. 
   

   The fact that she is leaving, so her beautiness and cuteness is leaving as well (kinda like poetic way of saying? I dunno)