Tbh how is naruto any different in that sense? Sasuke shut him down countless times, heck he put a chidori right through his heart, hellbent on killing him. If not for the kyuubi healing naruto would be dead yet he still runs after him screaming his name. Sasuke attacks him again at early part 2 and was going to strike him down with his blade yet naruto cries after that and still is hellbent on bringing him back to the point he begins training for frs. Naruto is just like sakura in that regard, he treated both badly but they still have hope for him yet sakura is the only one being called out for that. All what you said can be easily reversed to Naruto and it would fit. Fact is they both saw sasuke as what he used to be rather than what he allowed himself become, Sakura wouldn't give up on him