1Remus left Grimmauld Place, stunned. He had not been expecting Harry to react like that. He would have that he, of all people, would understand. Instead, he disagreed strongly and became furious with Remus.
Somewhere in his heart, Remus knew that Harry was speaking the truth. Remus shouldn't just leave his wife and child like that. James wouldn't have wanted Remus to stick by Harry, he would have wanted him to protect his child and wife. He should have guessed that Harry would have hard feelings about Remus leaving his child. After all, that's what James had done to him. It hadn't been James' fault but he had left Harry.
He should go and talk to Tonks, Remus knew but he couldn't. What would she think of him now? He was a coward. A coward for leaving his wife and unborn child after he had promised not to. A coward for throwing Harry against the wall. There was no way James would approve of that.
He should have stayed at Grimmauld Place and talked it over with Harry. Maybe after he explained Harry would understand. He didn't want to go with him for his own reasons, but to protect Harry as James would expect him to do. His own child was unborn yet and his wife was safe at her parents house. There was no reason why he couldn't have helped them and then returned to his family.
But even as he thought it, Remus knew it wouldn't work. He would be too worried about Tonks. He would feel too guilty for leaving her alone. Something awful could happen to her or their child and he would never know. He could see now why Harry had gotten upset. What kind of father would leave their child before it was unborn and not be full of guilt?
He suspected Harry might have known what would happen if he went. Harry probably thought Remus would miss Tonks too much. He didn't know how Harry could know these things or even think of them, but he knew that Harry was right. That boy was more like Dumbledore than he would even imagine in his ways of thinking and knowing things.
Remus sighed. He knew he needed to go see Harry. To apologize for acting so horribly and for throwing him against the wall. They probably wouldn't be staying in Grimmauld Place much longer but he hoped they didn't leave before he reached then. Before he did though, he needed to talk to his wife and apologize for being such a coward.
With a soft Pop! Remus apparated to the one spot he hoped Tonks would be.