the problem is that naruhina is like sasusaku: one sided love. this is why it is possible to love narusaku and sasuhina. naruto and sakura have a strong relationship that can turn to something more. sasuke never love sakura; may be with friendship intent but not for love purpose. then sasuke and hinata can MEET if sasuke comeback; cause hinata is a close friend of naruto. they can gradually know each other and eventually fall in love; because naruhina and sasusaku have their chance and lost it.
well i can not find someone who can tell me that this is not logic. p.s: sorry if I made some mistakes. english is not my first language.