Proper Way To Address A Wedding Invitation

Me and my girlfriend have been going out for 41/2 years now. We were suppose to get married 6 months ago but have been having some problems and our wedding was called off. She has recently been invited to a wedding and and invitation was address in her name and guest. We have never broken up or have been separted. We have stayed together though everything and were still a couple. Should they have address the invitation this way or should they have include my name also.