At 18 yrs. old, I would have kept hitting him until he was unconscious, just like she did. I would have wanted him unconscious so he couldn't get to me again. At 18, I would not have known I might be killing him, I was stopping him, not killing him.
There are movements a woman can use to get away from an attacking man, especially if he doesn't have a gun. One of the best methods I have read (if you the woman have no gun/knife/maybe pepper spray in your hand and ready to use), is, lift up your feet and you fall to the ground, out of his grasp. He will be surprised. Then, run away while he is still surprised. He likely will not run after you. I also read the woman has more power for herself on the ground dealing with him than if you are standing up where he has most of the power over you. Now, I know there are ways to attack the man while standing up but those are fast movements the woman would have to do and that is likely not going to happen if he is much larger and stronger than the woman. I would do the drop to the ground immediately and create surprise and get out of there.
It is terrible that some men use their strength against a weaker woman. We women live with that possibility all our lives and we have to be "aware" of our surroundings all the time.