She had always liked to read. Before the war, she could lose herself for hours in any sort of book before something in the real world would pull her away. But now the war was done and she was a different person. Her parents were still in Australia. She would leave them there, maybe forever, but definitely until she was sure all the stray Death Eaters couldn't find them. The first week after the final battle was spent cleaning up Hogwarts and burying the dead. The next week, she went to her parent's home and slept for days. She relished in the ability to sleep in, bathe leisurely, and eat meals whenever she wanted. She was blessedly alone. Not that she didn't love Harry and Ron, but she was an introvert at heart and desperately needed alone time to cope with her grief and the upheaval her life had been for the last few years.
Anxiety attacks were coming more frequently these days. One moment she would be stirring soup on the stovetop and the next she was shivering with sweat beading her brow, frantically thinking about things that were beyond her control. To calm herself, she grabbed a muggle romance novel from her mother's bookshelf and began to lose herself in the frilly, fluffy story. It felt wonderful. Scratch that – the lack of feeling itself felt wonderful. No stress, no worries, no grief. Losing herself in a book blocked out all of the other feelings, leaving her with a quiet sense of euphoria.
She finished that book and immediately started on another. She slept a few hours that night, too wrapped up in the novel. The next day repeated the same pattern. She brought her next book into the bubble bath and stayed in there for hours, turning the hot water nozzle with her toes when it got too chilly. She dressed in her pajamas again and curled up on the couch. Throughout the day, she forgot to eat but felt no hunger. That night, she forgot to sleep but felt no tiredness.
At one point, she thought she heard a knock on the door but she was too far into her own world that she wasn't able to come out. She knew, deep down, that this wasn't going to work. She needed to face her fears and anxieties and grief. She couldn't just shut down and avoid the world. But the thought of going outside made anxiety crawl up her spine. Her cheeks tingled and she felt vaguely nauseous. She couldn't do it but she could lose herself in the happy promise-filled world of fiction. Soon, she promised herself. Soon she would emerge again but for now, this is all she could handle.
Note: After a particularly bad time in my life, I found myself like Hermione losing myself to the real world. Reading is how I coped with no longer being able to function as I should have. It's not glamorous and it could have been a lot worse (drugs, alcohol, etc) but it helped me survive for the first few months when I didn't think I'd have the strength to do it.