Hermione stayed behind him, giving him space, but she didn't make any motion to leave either. "No, Ron, this is where I need to be right now," she said with a shaky voice. She'd made the mistake of leaving him alone all week, she wasn't going to continue that. "You don't have to explain, I don't care why you did it, it doesn't matter."
She looked off to the side then, and let the silence stretch a bit, purposefully not intruding on him any more than necessary, but she was going to make her point that they were in this together and she wasn't going to just walk away from him, no matter what the rest of the group might need.