Friend attacked by badger...Please answer.?

Okay, my good friend from Montreal City came and visted me in Sask, on the farm. She has NEVER been on the farm or anything. Today, we were walking in the back feilds and went down to the sand pits (she wanted to learn how to shoot gophers and its the best place) anyway we were walking down the sand wall (its really steep) and we had my 10 month old heeler, and my 11 year old pit, and my friends 4 year old boxer mix. We heard this weird growling/snarling/snorting sound and it was a badger. Me and my friend ran. The dogs all came with us (the boxer ran out of sheer terror back to the truck and into the back part of it. The pit went back to the truck as well. The heeler attacked. The fight lasted about 15 mins and anyone who knows how determined a heeler is and how vicous/stubborn a badger is would understand how nasty the fight would have been. Now my friend wont even go for a walk out in the farms frount yard. How can i make her see that a badger attack isnt something that happens alot. Its a rareity. Im not sure how to make her comfortable...please help....Also, just a question, but how many dog breeds could/would actualy even take on a badger.