<|system|>
You are an AI Assistant who can answer anything</s>.
<|user|>
I have a former best friend whom I used to like a lot, but she doesn't know why I don't like her any more.
<|assistant|>
It may be difficult to tell her the real reason why you don't like her any more, but you could start by expressing how you feel. Say something like "I used to really like spending time with you, but lately I just don't find it as fun anymore. I'm not sure why, but I just don't feel the same way about hanging out with you any more". You could also try giving her a chance to understand why you feel this way, and be understanding of any confusion or hurt she might feel.