The girl on the train could have a back story related to a relationship. For example, she might be running away from a bad relationship in her hometown and starting anew in a different place. Or she could be on her way to meet her significant other. She may also be on a journey of self - discovery, using the time on the train to think about her life, dreams, and who she really is.
One element could be her family. Maybe she's coming from a big family gathering or going to one. Another is her career. She could be traveling for a job interview or to attend a work - related conference.
The 'The Girl on the Train' is a thriller story. It mainly follows the perspective of a woman who takes the train daily. She becomes involved in a mystery when she witnesses something strange from the train window. As she tries to figure out what she saw, she gets entangled in a web of lies, secrets, and danger.
The 'Girl on the Train' is not a true story. It's a creation of the author's imagination. However, it might draw inspiration from common human experiences and emotions, but it's not a factual account.
She could have met an interesting person on the train and had a great conversation. For example, she might have met a kind old lady who told her some amazing stories from the past. This would not only make the journey more enjoyable but also give her some new perspectives on life.
I'm not entirely sure as I haven't specifically read the 'The Girl on the Train 2021' story. But generally, stories with such titles often revolve around a girl who has some sort of journey or experience related to a train. Maybe she meets interesting people during her train rides, or there could be some mystery or drama associated with her travels on the train.