This is the kind of tragedy where I feel an immense amount of sympathy for everyone involved, and yes, that includes Eri. I don't think a lot of people understand how difficult family pressure can be to resist, even when it's just a passive attitude, let alone if there's an active campaign by the family to keep you on track.
Thankfully, arranged marriages aren't the norm in the West anymore, and they don't seem to be especially common in Japan either. But what Eri did here was still very understandable.
