I know it's taken me some time to get back to you with feedback, but here goes. I read your story right away and I've been thinking about it a lot. Your characters have really stuck with me, and so, to answer your question, yes, there is enough depth to them, especially Sue.
I don't think it's disrespectful at all to say the receptionist looked like Dolores Claiborne, but it would have been disrespectful to say her personality was that of Dolores Claiborne, which you didn't do at all. However, the fact that she looked like her causes the reader to wonder about her personality as well, which is interesting, but not the same. So, it worked for me!
As far as choppy goes...it seemed very moment to moment, definitely, but fit well, and at the same time seemed quick-flowing, like a whirlwind.
I am confused as to why you didn't like the ending. It was a bit abrupt, but I liked it that way. Unless there is more that needs to be said, I wouldn't change it.
Thank you for sharing your story.