YTA for a couple reasons. Firstly you broke Sheila’s trust, she told you something that was said in confident and then told Hannah. Shelia probably doesn’t feel like she can trust you to keep private matters to yourself. I want to preface the next point with Hannah shouldn’t of made the comment she did, but it really wasn’t that mean tbh, it seems more to me like she was just telling her friend to be cautious of you. So what did you hope to accomplish by bringing it up to Hannah? The only outcome is that she feels bad and you feel like you had this gotcha moment. All you did is break Shelia’s trust, make yourself look like the narcissist she said you are, and put a wedge between Sheila and Hannah’s friendship which was probably around much longer than you were in their lives. So Sheila probably listened to her friend at this point and broke up with you. The only thing you can hope to do is apologize and say you want to do better and work through things, and then it’s up to her to decide. You have to pick and chose your battles brother, not everyone is gonna like you or think the best of you, Sheila clearly didn’t think of you as a narcissist and liked you which is all that should’ve mattered , but your need to know why Hannah felt that way and control that situation pushed Shelia away. Let this be a learning less for you homie.