this, young padewans, is what constitutes as the author's limited knowledge on what 'love' is...
Sasuke and Sakura are the 'Male Lead' and 'Female Lead' parodies, the only reason they 'love' each other by a story standpoint is because 'THEY MUST!', just like Kagome/Inuyasha, Usagi/Mamarou, Marlene/Yugi, Shiki/Mikiya, etc. etc. etc. every lead couple since the dawn of time...
now, since they are a 'parody' of such, its not going to make any sense beyond 'they must' while other series like to actually equate some rational to this...
NOW! not looking at this from a literary standpoint and actually them being 'people'... well, at first when they were kids Sakura took an interest in Sasuke, then got defensive when it was revealed her friend liked him too, as you can see from canon start onward, Ino got progressively bored with the concept and moved on, to her it was just a passing interest, as Ino seems to be that 'valley-girl insert' (which amuses me) while Sakura went on to full on 'obsession'... her 'interest' evolved into 'crush' which evolved into 'obsession', at this point the only reason i'd call it 'love' is because its the only thing that makes 'sense'... shockingly, as you get older, young padewans, this makes eerily more and more sense, especially if you have experience in overall messed up relationships... Sasuke is simply a focal point Sakura, like a whole lot of other people in the series for some reason, can't get over, though her 'love' for his is strikingly the most sympathetic... Sakura, as i've whined about in that other thread, is surprisingly 'normal' for the world she's in... she's tofu, it'd only make sense she continues on the blinding path of her archetype...
course, she's crazy, they all are, but what are we gonna do about it... Karin's an extra-special-dose of crazy...