I've heard the phrase "Oh, well..." used in the same tone as "Bless his/her heart!"
It generally means "Oh, well, I don't have any polite words to say, so I'm just going to not say anything, but you're being judged."
Also, when my great grandmother would say it when I was young (mostly in response to news stories), I thought she was saying "Oh, whale." I was really confused.