Who is in the wrong?

2 online friends. Never met in person.

Emma posts a message on her Facebook page saying she feels alone and like she has no support offline.
Anna replies 'Umm.' When Emma asks what she means, she keeps liking the queries but not answering the question.
In the end, Emma goes onto facebook messenger and asks Anna what she means. Anna said she was hurt by what Emma said about having no offline support as she felt Emma had not considered her. Emma says that Anna is an online friend and they have not met in person. She says she is disappointed in the way Anna has approached this and that she felt like she was shamed on her Facebook page.
Anna says that Emma has overreacted and that she did nothing wrong. She says Emma is a user.

What would you make of this?