Syag,i think the catch all phrase you’re referring to is ” the personalities didn’t match”
Not feeling anything is a different story. It begins with the assumption that they’re supposed to feel something, which ia an error and has prevented many successful shidduchim.
I also have no idea what talking to a woman I don’t know about a shidduch has to do with mixing genders. It’s not a social conversation.
Perhaps assuming I’m single also grants a measure of ability in your mind to dismiss my observations on the nature and behavior of women?