May i ask your opinion on this?
One thing I find fascinating and hypocritical is that many people hate Sakura for loving and marrying sasuke but don't have that same reaction with karin. People go on and on how two characters that attempted murder on each other shouldn't be together, but at the SAME time, ship him with karin. By all accounts, they shouldn't be shipping them together. But for some reason, it make sense to them? And they mostly state that karin had a reason to like him? But he almost killed her. And was almost successful. Why is murder okay or even justified with sasukarin and not sasusaku?
to be honest with you, i don't really know... i try to avoid the business of puzzling over why people in the naruto fandom do anything... but there are some textual reasons that may make sasukarin a less "problematic" option than sasusaku (not that i have ever in my life cared about that)
i will say that sakura's attachment to sasuke is perhaps a more subtle thing than karin's. karin straightforwardly trusts him first and foremost because he intervened to save her life, risking great harm to himself, when they were competitors during the chunin exams. no one would have faulted him for standing idly by. of course, sakura has also been saved by sasuke, and encouraged, and supported, but it's complicated by her initial crush, which was as profound as most 12-year-olds' crushes get (which is to say, not very). there's also not a clean break between sakura's childlike infatuation and sakura's genuine love and care for sasuke -- the latter emerges before she's evolved past the former. in karin's case, her interactions with sasuke prior to the land of iron are completely recontextualized by the chunin exams flashback. i sort of see why people would view karin's affections more charitably, even though i think this is a misread of what sakura's got going on in part 1. (speaking mostly to the fandom here on tumblr -- the dudebros are pretty obtuse about both karin and sakura)
another distinction is that once the war arc sees both taka and 7 reunited, sasuke falls back into old patterns very quickly with all members of the former (karin included -- she even receives an apology!) as well as naruto. kakashi and sakura, meanwhile, get the cold shoulder. kakashi is also hardened enough that it doesn't, like, visibly get to him so it does come off a little bit like sasuke hurling shit at sakura in at least two separate instances for no apparent reason while she is too saddened by the state of things to respond. the persistence of karin's feelings seems reasonable to many simply by comparison.
that's my answer to your ask but i do want to elaborate on that last point to address the sasuke and sakura(/kakashi) dynamic during the war arc, because someone must.
i've seen people cite 1. sasuke just loving naruto more, and differently and 2. his myopic focus on saving the world as explanatory factors but i don't think either accounts for his harshness.
i suppose i could see why it would be difficult to stomach a sasuke and sakura reconciliation if sasuke's attitude towards sakura is so much more frigid than towards naruto despite his emotional neutrality... except, of course that there is no emotional neutrality here. like, ever. the sasuke fandom on tumblr is perplexingly averse to admitting that he has a bad habit of emotional repression/concealment/compartmentalization, to the point where i've seen the notion ridiculed multiple times by fandom-acclaimed sasuke understanders, even though it's one of the most textually concrete facets of his character. it's fundamental. (from what i've gauged this is a response to the most annoying contingents of the ss fandom claiming sasuke hides everything ever and thus has had a crush on sakura since he was 5 years old... nonetheless an overcorrection. and demonstrably incorrect.) anyway, he's repressed a great deal of emotion by this stage with relation to team 7 and what occurred at the land of iron. i feel pretty confident making this assertion because it's evidenced later following his battle with naruto, where sasuke's greatest source of gratitude towards naruto heartbreakingly, is that naruto never tried to kill him. even though, as he seems to believe, "everyone would always want to kill me"
sasuke speaks of everyone but there are like 7 people he holds in any regard over the course of parts 1 and 2. which murder attempts, aside from the obvious (itachi), do we think are the source of his distress here...
(to expand, it's not the specificity of a murder attempt that stings so much as what it represents: that two people he held dear resolved he could only be addressed through violence. i do of course think this falls flat on some level because sasuke is lying there with his arm torn off but, alas)
i think this resentment over perceived intent to kill him colours his attitude towards kakashi and sakura (even though he would not even admit it to himself) and it's all the more upsetting because sakura never could have! anyway, a lot of sasusaku is uncharacteristically subtle by naruto standards (and people also have brainworms about them and both characters individually), and as a consequence this element of their part 2 relationship is overlooked by just about everyone.