If a woman and a man from two feuding families elope, do they bear some responsibility for the
resulting carnage?
IMO, they do.
I refer to the Grangerfords and the Shepherdsons in HUCKLEBERRY FINN.
The Grangerfords and the Shepherdsons
Huck and Jim's raft is swamped by a passing steamship, separating the two. Huck is given shelter by the Grangerfords, a prosperous local family. He becomes friends with Buck Grangerford, a boy about his age, and learns that the Grangerfords are engaged in a 30-year blood feud against another family, the Shepherdsons. The Grangerfords and Shepherdsons go to church. Both families bring guns to continue the show, despite the church's preachings on brotherly love.
The vendetta comes to a head when Buck's sister, Sophia Grangerford, elopes with Harney Shepherdson. In the resulting conflict, all the Grangerford males from this branch of the family are shot and killed, although Grangerfords elsewhere survive to carry on the feud. Upon seeing Buck's corpse, Huck is too devastated to write about everything that happened. However, Huck does describe how he narrowly avoids his own death in the gunfight, later reuniting with Jim and the raft and together fleeing farther south on the Mississippi River.
http://en.wikipedia.org/wiki/Adventures_of_Huckleberry_Finn#The_Grangerfords_and_the_Shepherdsons