This question seems to be incomplete. However, there is enough information to find the right answer.
Answer: Melinda is suffering from depression
Step-by-step explanation:
Despite the lack of context, we can infer that the character from a book, named Melinda, sleeps all the time, wears drab clothes and black nail polish. The dark tones in her appearance could be related to a taste for hard rock music. However, that wouldn´t explain the constant sleep. We don´t have information about any past trauma, but even if we did, Melinda´s behavior doesn´t seem that of someone in recovery. Melinda simply being lazy and having a taste for wearing dark clothes is too simplistic. And being lazy is not the same that sleeping all day. In the end, someone who sleeps too much is most likely going through depression. And the dark clothes and nail polish, also point in that direction.