Kaew Tah Pee (2006)

Both have accidents that cause blindness and the female lead ends up as caregiver. Both have male leads regain sight. Both have some level of misunderstandings in the MC developing their relationships.

Both are about a marriage of convenience contracted between the main couples.

Both (one to a lesser degree) have to deal with medical blindness and the caretaking of one of the main leads by the other lead.

Both have outside forces plotting against the relationship.