They both have blood on their hands. This is still a poor comparison, and your arguments and rebuttals disagree with each other.
Much like Jaina losing Theramore doesn’t excuse her attempt to wipe out Orgrimmar, Sylvanas “not having friends” (more like not desiring anyone) and undeath are paltry attempts at absolvement.
The key difference between these two is that Jaina at least understands what she did was wrong. She’s at least tried, several times, to rise above her hatred by working alongside the Horde leaders for the greater good.
What has Sylvanas done in any possible way to atone for all of the sick evils she has committed?