It wasn't Team 7 anymore, and it would not be Team 7 until there were no missing pieces. Because Sasuke had broken them and they still needed fixed.
Naruto had promised to bring him back, for Sakura, for Kakashi, for himself. So he left the Leaf, and he trained and trained and trained under Jaraiya, until he couldn't move any more. Because he had to fix the fucking mess they had become somewhere along the line. And he had to kill those Aktsuki bastards, because they wouldn't stop until he was dead anyway, so it wasn't like he could just let them keep coming after him. And he had to get stronger to protect the Leaf and become Hokage because he just has to believe it and push through until he could finally do this.
Sometimes, he stared at the picture on his desk, and hate himself for it later. He would watch Sakura smile and Naruto be-well, Naruto-and Sasuke keep looking aloof and uninterested. And Kakashi would miss it because at this rate there would be no one left to nail his door shut like he had done for others. And even if there was, he planned to make it a hell of a long time later. Because he still had things to do and teach. Because he would always keep teaching them because they were and always would be his students, that wouldn't change no matter how many times he told them to drop the sensei, your adults now and I can't be your teacher forever.
After he had left, Sakura made a vow to herself. She would get stronger, and she would help Naruto drag his ass back by his hair if she had to. So she found tutelage under Tsunade-sama. They had always left her behind, and she had let them because holding them back just seemed wrong when they were so much stronger. And so she got stronger so that they would all stop leaving her behind, they would have to. Sasuke, Naruto, Kakashi, everyone. They wouldn't be able to leave her behind anymore-and she wouldn't let them-because she could keep up and she wasn't that weak little girl from three years ago.
And then...All Sasuke wanted was revenge, and to restore his clan and go home so he could rest for once in five years. Because he was tired of dealing with Karin, even though he would miss the group he had established after killing Orochimaru. And even though his brother was dead by his hands-he had always loved him, he was his brother-there was still revenge. Because he wouldn't have been dead, and he wouldn't have massacred their clan, and he wouldn't have had to become what he had if it weren't for his home. So it wasn't the village he wanted to destroy, it was only the people who had caused this. Because, secretly, he missed obnoxious Naruto and all-too-caring Sakura, and their always late sensei, Kakashi. And he just wanted to stop running and fighting and rest.
Because Team 7 would not be Team 7 until he returned to Konoha. And even then, they would always be a little bit broken.