I disagree. She's been able to stay composed and calculative due to her drive for revenge and to keep Helis safe, as well as her not having as deep feelings or attachments towards most people... but Helis is different. He is the drive for her whole plot of revenge, she still loves and cares for him, and she doesn't want anything bad to happen to him. It makes perfect sense for her character for her to jump in to save him if she sees him in danger, especially when she knows he no longer has his divine powers to help him.
As for the swordfighting, I only caught up from ch 48 to now (61) so I don't remember if it was discussed in this life/if we were told or shown she had practised it, but we know that she must've been very skillful with it in her past life. After all, she was the one who invaded the royal castle and killed Ianfried. These are the things I assume you're thinking about when you say it's out of character for her, as you didn't provide any other context for your comment ╮(￣▽￣)╭
Okay, that was out of her character! I will stop here.