Part of the essential spark that is Khavi is her dedication to duty. It seems to me that over her longer than long life span she has become consumed by it. In the end her duties as chief are what defines her. This makes her a good chief for her people but makes it hard for her to make emotional connections outside of that huge boundary.
I think that Tyldak is good for Khavi in that he's showing her that there is more to life than her duty as chief of the Go-Backs. There are more sights and sounds and colours out there than she was allowing herself to see. I think that Khavi after Tyldak will be a much more rounded person than she was before. I don't see them as lifemates, which has more to do with Tyldak than with her, but I do think they are good for each other in that "I didn't stay with them for life, but they changed my world and I'm forever grateful for them."
One of the reasons that I really like Khavi is that she challenges me to see things from her perspective, she makes me renegotiate my boundaries. By truly empathising with her the many shades of grey in do or die situations have become clearer to me. Both her and Krim have taught me that you don't have to be soft to be a woman, and for me as I am not really all that soft...is a wonderful thing to see. :)