That's much more likely to be truth. I think she loses herself in the fight, doing irrevocable things, then she feels immense guilt once she is back to her senses. That doesn't mean she enjoys what she does during a hard fight, but on the contrary, she feels like a monster because of that.
I'm telling this once again, Els is a genius erudite. She wants to learn and tell, and make the world a better place. Yet, she did things in the past, which made her feel like a monster.
The fight on the beach was under control through and through. Which is the reason why we didn't see her in a frenzy. She instigated / couldn't defuse the fight with intimidation, because she was pent up, and because Valentine was there. I really think she wouldn't get into that fight if Valentine weren't there, not out of fear for her own safety, let alone the girls' safety, but for the safety of those two idiots. That fight is the indicator of how much Els trusts Valentine, not hold his own, but to hold her back if she went berserk. It was a safe opportunity for her to blow off some steam, thanks to Valentine. Because unlike Els, Valentine is a professional up fucker, who is always in control, during any fight. He don't even get nervous or excited in his fights, he just keeps talking "like it's a sunday dinner".
I really believe they are perfect for eachother.