The Girl on the Train Betrayal

We're not sure exactly what Megan means in this therapy session, but perhaps this is her way of telling her therapist that she's committing infidelity… and while she's at it, she'd be happy to… to… to, um, do so with him, too.

Rachel is especially sensitive to infidelity, so when her dream couple ends up not being perfect, those old pains resurface.

Rachel takes this betrayal extra personally. We're surprised she doesn't go try to have a word with her.

Megan only feels like this because of how Scott constantly invades her privacy. He thinks her entire life is his business, so if she talks about her life with someone else, it feels like a betrayal.

Megan is considering leaving her husband here. She has had an affair, and instead of owning up to her betrayal, she considers running away.

Remember when Rachel felt so betrayed by Megan kissing another man? Oh how things change—Rachel is now seeing the other man, Dr. Abdic, as her therapist. And after he's suspected as a killer. Looks like Megan doesn't have a monopoly on betrayal.

Maybe this is the ultimate betrayal in the book. The way Mac treated Megan led to her abandonment issues, which eventually led to her affair.

It's true that you can't help how you feel, but we think it's ridiculous for Rachel to ever feel like she's betraying Tom, a man who cheated on her and left her for another woman.

Tom took advantage of Rachel, betraying her trust by lying to her about what really happened during her blackouts. That's super low.

Here is when Anna finally realizes that Tom is betraying her, too. Tom isn't selective about who he betrays, and he pretty much screws over every character he comes in contact with in the book.