In contrast to her contemporary Sally Rooney, I finally feel like I found a book about a clearly flawed character that does not end up romanticising their behaviour. Frankie is clearly depressed and struggling, her need for solitude becomes the grounds for an extended meditation that becomes the entire plot. She is selfish at times, rude and blunt and there's little character development as she refuses treatment for her mental health issues and confides herself in her own thoughts. Her isolation and embracing of a deep intellectualism to justify her depression makes her not a lovable but a pretty realistic character. It doesn't mean I did not feel empathy for her, far from it too many instances were way too relatable. However, and in contrast to Rooney, people just dont flock around her and try to heal her and cling to her despite how awful she is, she ends up alone and lost, just as she begun the novel. 
I believe this is extremely important when we talk about the consequences of mental health and narcissistic tendencies mixed up together. Making it look (in fiction) that despite being sometimes an unbearable human and at times rude and pretentious people will forgive you and love because you are so rare an unique is utterly unrealistic. 
I think Baume did a marvelous job reflecting the reality of mental health,  its hardships and loneliness.