Common (not actual) libertarian thought rejects all violence, even when when the
rejection of violence is the rejection of self-defense- which is anti-life, and thus anti-libertarian.
Whether a bystander is wittingly or naively protecting your attacker, you have the right to preserve your life, even at the expense of said bystander.
Now, there is an argument that if the bystander is younger than you, and thus has longer to live, that accepting death (in order to allow the bystander to live) is the pro-life (and thus libertarian) option.
ONE CAN SIMULTANEOUSLY BE ALT-RIGHT AND LIBERTARIAN.