Aelia was a nice girl, with a very considerate mind, given that is why? People tend to exploit her kindness.
Most of the time, she does not share her secrets and problems with others, which had created an invisible wall between her and people. That made, people think, that she is putting on a tough front to reject them, and their friendship, the impression deepens and they all start to think that they had to earn their friendship from her.
This kind of sentiment is something, that distances her from normal people.
Chen was one of the kind, who did not mind, her actions to avoid, at all and even pester her, to let him stay around to help her out from time to time. Just like a friend should have, which is something a normal person, would not do until they are in love.