She's got no direction in her life and she's a little down because of it. She feels like she should be doing more and feels distant from her husband. She doesn't even know why she came to Tokyo. In short, she's questioning her life.
In another city where maybe she knew people she could have people to talk to. Or if she spoke the language she would feel more comfortable travelling and visiting different places. Tokyo is a little intimidating to the first time visitor especially if you don't speak the language. So she spent a lot of time in her room where it was "safe" and she could try to figure things out.

Yes, I have.

@kane
have you been to tokyo before?

I thought it was because she didn't know anyone in Japan, her boyfriend was always busy with work, and she didn't want to go anywhere alone - all of which made her feel emotionally distant despite being in an amazing city.