He knew there was something wrong, he didn't know that it was him though - and even though Ginny seemed adamant, he didn't believe her for a second.
"I'm not treating you like you're going to break Ginny. I've never done that." And then she was shouting at him and he was at a loss, not knowing where it was all coming from.
Neville eyed her carefully, his hands on his hips and being just as stern as she was. "I know full well you can take care of yourself Ginny. I only tried to warn you - he was coming at your back... and how in the hell does that mess anything up.
Then, what she said both confused him and made him feel like there was a huge ball of ice in his stomach. She had hastily thrown a suitcase on the floor and was flinging things into it haphazardly. "What?" Neville stomped over to where she was and took the suitcase up and threw it clear across the room. "I don't know where this is coming from, or why, but I've never known you to quit anything, you won't let anything get in your way and I'll be damned if I let you quit me when I know it's something else." He'd never been as angry or upset with Ginny as he had been in that moment - he knew her, and she knew him - and that's exactly why he couldn't let her do this to herself, cover up whatever was bothering her with something else.
"I know you, and if I even thought about trying to protect you, I'd have to protect my damn self because I know you wouldn't have it. So spit it out Ginny." Neville reached and took the shirt she was holding from out of her hand and held onto it tightly, squeezing his anger and frustration into it.