I can definitely see that, though I’m only on the 4th book, so I still have a lot more about her to discover.
In addition to all you said, I do think there’s a general tragedy and lack of a chance for redemption to anyone who takes their dark oaths. And since I’ve been reading some of the books about the general WoT world, I know how Verin’s story ends, and I found her story to be very tragic too.
Lanfear didn’t seem to have a choice when she took her dark oaths. She didn’t know what she was unlocking, and even though it was her drive for power that caused her to do it, she seemingly had good intentions behind her desire to access this power too. But once the Dark One was out, it was take the dark oaths or die. She became calloused and violent, but when you know that revoking your dark oaths means eternal soul death, it would be hard to feel anything but hopelessness.
So yeah, I agree she is tragic. But also to another commenter’s point, most serial killers have backstories that are terrible. Still though, I think that anyone who can be so violent has had something happen to them that is tragic to lead to that type of aberrant behavior.