I believe he loves Sakura but is not in love [anymore], a huge difference. Despite the random silly date jokes, he knows very well Sakura's heart is still for Sasuke & is quite content with this.
Naruto's love & relationship for Sakura is like Jiraiya's love & relationship for Tsunade. Even though Jiraiya is an absolute pervert, he loves Tsunade but has come to an acceptance Tsunade's feelings will never be mutual.