She could also be sad and withdrawn. Ginny might think that her brothers' actions mean that there's no hope for her and Harry. So she might start to distance herself from Harry on her own, not because she wants to, but because she feels pressured by her brothers.
Ginny might be angry. She could feel that her brothers are interfering in her personal life and not respecting her feelings for Harry. She might confront them directly and tell them that it's her choice who she wants to be with.
One possible reason could be that they see Harry as a friend but worry about Ginny getting hurt. Harry has a dangerous life, and they might fear that Ginny could be in danger if she gets too involved with him. For example, with Voldemort constantly after Harry, they may not want Ginny dragged into that mess.
Alternatively, Ginny could be very mature about it. She might respect Harry's decision, even though it hurts. She could choose to step back and give Harry the space he seems to need while secretly hoping that he will change his mind in the future.
Ginny would most likely be extremely happy. She has deep feelings for Harry, so his proposal would be a dream come true for her.
Ginny might be overjoyed. She could blush deeply and then give Harry a big hug, telling him she feels the same way.
Ginny might be heartbroken at first. She could retreat into herself, spending a lot of time alone in her dormitory or in secluded places around Hogwarts. She may cry a lot and avoid socializing with their mutual friends.
She might be hurt at first. Since she's pregnant, her emotions could be more fragile, and Harry's anger could really sting.
She might blush. Since Ginny has feelings for Harry, his stare could make her feel self - conscious and her cheeks turn red.
Ginny might initially be heartbroken. She could retreat into herself, feeling betrayed and confused. In some fanfictions, she may cut off all contact with Harry immediately.
On the other hand, Ginny might secretly be a bit flattered that Harry is so possessive over her. But still, she would probably try to stop the situation from getting worse and make Harry understand that he can't just go around punching people because of her.
She might get angry right back. Ginny is a strong - willed character. So, if Harry yells at her unjustly, she could stand her ground and yell back, not willing to be pushed around.