Horrible, horrible mrsruffallo
I had something similar, in that I got an abusive email from the husband (admittedly very wierd husband) of my friend, who I had not known for long.
It fills you with horrible cold shock when this sort of thing happens and you doubt yourself (that is obvious from YOU wanting to phone HER today) You must not phone her, she should phone you. Even if, and you didn't, but even IF you had ranted all evening about your job, so what? This is your friend and you arfe allowed to, plus you have invited them round for dinner.
To be honest, I gradually stopped contact with my friend, her lack of sticking up for me etc, made me not trust her.
Poor you, I hope you have a nice weekend and try not to let this ruin it.
By the way, the fact you said 'thank you for letting me rant about it' shows you were very self aware and is also the sort of thing I also say after telling a friend woes. It indicates to me that you were a lovely host.