On the drive by hand shakes it could just as easily be - see you in an hour for dinner, as being 'cold'.
We have threads on the BY about hand shakes and reading meaning into them and it always strikes me as a lot of noise about nothing. Only very occasionally do you get some sort of confrontation or obviously angry moment, or alternatively a drawn out very friendly exchange - everything else is just idle speculation by fans with too much time on our hands! :-)
As for last night, I suspect McGraw had a lot on her mind re her player's health and anything read into a handshake is particularly meaningless.