Grendel's mother, though animalistic in her methods is in many ways is doing the right thing. When I say she may be following the honor code, there is no way to tell; the attack on Heorot may have been just the first of many, or it my have been instinctive. Who knows?.
As I said before, Beowulf should not be talking to a king this way, weak king or not; after all, in their society kings were ordained by God. After Hrothgar gives in to despair, mourning the death of his counselor Beowulf says to him, "Wise sir, do not grieve. It is always better to avenge dear ones than to indulge in mourning. For every one of us, living in this world means waiting for our end. Let whoever can win glory before death. When a warrior is gone, that will be his best and only bulwark- (1383-89).
This first half is seemingly harmless, Beowulf sharing some of his own courage and convictions with the king. However, I think that in saying all men live to die, Beowulf made it true for himself; he stumbled over his own mortality. Beowulf realized that he was only human, a powerful human with some supernatural abilities, but human nonetheless. Even though he'd be leaving behind a great legacy, dead is dead no way around it, no coming back from it, the end. Also, even though the king is grieving, he shouldn't be so expressive or so free with his emotions, a king, in Beowulf's mind, should be strong for his people. His despair is like a cancer to his community, who after years of horror at the hands of a monster, finally have a small glimmer of hope to cling to.
"So arise, my lord, and let us immediately set forth on the trail of this troll-dam. I guarantee you: she will not get away, not to dens under ground nor upland groves no the ocean floor. She'll have nowhere to flee to. Endure your troubles to-day. Bear-up and be the man I expect you to be- (1390-1396) .
In this second half however Beowulf is a bit more ferocious.
