So, (btw I haven't read the novel this is just me theorizing, which is why I'm not spoiler tagging it) who wants to bet that Duchess Nürnberg has anime mom disease and is dying, and died in the previous timeline which permanently ruined the relationship between the Duke and Nora? Either way I hope things don't turn out the same this time around.
Also my guess as to why Ludovica and Shuli look so similar is because they're cousins. In an earlier chapter, Ludovica was mentioned as being the daughter of a baron (the lowest rank on the totem pole, for our purposes) while Shuli's birth family holds the rank of Viscount, which is only one rank up from Baron. Given nobility was more likely to marry close to their rank, I don't think it'd be much of a stretch to say that Shuli and Ludovica have a shared ancestor somewhere along the line to explain their physical similarities, but I don't think Shuli is Ludovica's secret illegitimate daughter or anything, lol.