It's a really big party! That's what they're planning! Willow spent all this time trying to track down your invite, it got lost in the mail. Don't even worry about it.
The huge from the previous page didn't last that long. Willow's not a hugger, and Laurens takes boundaries very seriously even when it's a matter of life and death.
Probably not the first time Laurens has hugged Willow because he thought she was dead, then been chastised for it later.