Question:
A man marries a paralyzed woman, does he have an increase in virtue–for example to take care of orphans?

Answer:
If he has an intention regarding this—desiring to guard her chastity, to protect her with this and spends on her, then Allaah does not withhold reward; rather actions are judged by intentions.

[source: see link with audio: http://www.sahab.net/forums/index.php?showtopic=136571%5D