Is the questioner considered remiss in her duty towards her parents due to their passing while she was abroad, even though they approved of her travel, or was being with her husband more appropriate given his need to work abroad?

What you feel about falling short with your parents is a natural feeling, and shortcomings occur from everyone towards their parents due to the greatness of this right. However, the occurrence of shortcomings does not mean the occurrence of sin. You are legally excused for your distance from them and your travel with your husband, as the husband's right takes precedence, and furthermore, it was with their consent.

The door of honoring parents remains open even after their death through supplication and seeking forgiveness for them, giving charity on their behalf, honoring their friends, and maintaining kinship ties that are only connected through them.