Use the rope to get Faye's bow and arrows to her. Have her fire at the boar as long as possible. She may be able to drive it off or kill it.
Use the rope to create a sort of snare with which to try to trap the dire boar.
Wait in the trees for a while, hoping the dire boar will eventually leave.
Have everyone climb down and attack the dire boar en masse.
Have Aelric use something else from your pack? (please comment details)