From my perspective there is one of two reasons. 1) She doesnt like you but doesnt want to seem harsh, may end the friendship (yes I know you mentioned that you can deal with rejection in the conversation but still. They are, after all, just words) 2) She has thought about being with you, but knows that its a bit wrong. Therefore she probably thought telling you she liked you too might make it harder for both of you to not start seeing each other. So in summary she either likes you or doesnt, same as before you told her (which is a bit of a bitch) but now she knows you like her, if it comes to a time where she thinks 'well f**k it' it will be a lot easier for the relationship to start. Havent really explained myself aswell as I could have but i need to get to work