LORELAI: Hey, you didn’t by any chance invite my parents, did you?
SOOKIE: Actually, I did.
LORELAI: Oh.
SOOKIE: And at first, I was really torn because I know you have issues with them, but it is your wedding and I assumed you wanted them to be there. Oh no, your mother told you.
LORELAI: Sort of.
Lorelai here discovers that her mother knew she was getting married because Sookie told her, bringing about a terrible argument between mother and daughter. To her credit, Lorelai doesn’t blame Sookie for her faux pas, possibly recognising that it was her own responsibility to tell Emily about her marriage first, and that she never explained the situation properly to Sookie.
The Annotated Gilmore Girls 