We know that (or I know that, and my headcanon of her yandere-ish character is from why she cannot get Sigurd but Gunnar instead despite the fact that she only swore to hold the former, but the latter plotted with Sigurd anyway, which is also her characterization in another series
ahem Fate/Prototype). Then again, as the Volsung saga dictates, her eyes are only and only for Sigurd, and seeing her alive in DxD means that there is also a chance that the original Sigurd will still exist in some form.
And no, Roland is confirmed dead, or Olivier, or Charliemang, or even Astolfo for that matter
