There certainly are some similarities. First, the wife in "Cat in the Rain" is disillusioned by her marriage to George. While she doesn't seem to have been married as long as Elisa in Steinbeck's story, she believes that her marriage has lost its excitement and that her husband doesn't pay her enough attention. Similarly, Elisa longs for attention and for someone to notice her femininity and to treasure that aspect of her character. While she most likely would not have griped to her husband about all the things she wanted (as the wife in "Cat" does), it is obvious from her conversation with the stranger that she longs to be appreciated.
Both women also rely briefly on strangers to make them feel special. The wife in "Cat" likes the way the hotelkeeper treats her and panders to her every wish. Elisa likes the way the stranger talks to her and how he seems interested in what she is doing and saying.
Finally, Kitty and Elisa depend upon elements of nature to brighten their tedious lives. Kitty wants the cat so that she can have something to be affectionate with, and Elisa cherishes her flowers because of their beauty and because they need her care.