Well, Sakura could have a complex set of reactions. On one hand, she has deep feelings for Sasuke, but being forced into marriage goes against her principles. She might be torn between her love for him and her own sense of self - worth. She could also be worried about what this would mean for her relationships with her friends and the village. In the fanfiction, she might start out by trying to reason with Sasuke, telling him that marriage should be based on mutual love and respect, not coercion. If that doesn't work, she may have to consider more drastic measures to get out of the situation, like seeking help from Naruto or other allies.
Sakura's reaction would likely be a mix of anger and sadness. Anger because Sasuke is trying to take away her freedom to choose in such an important matter as marriage. Sadness because she had always hoped for a relationship with Sasuke based on love and mutual understanding. She may cry and tell Sasuke that this is not the way to build a relationship. Then, she would probably try to use her medical ninjutsu skills to defend herself if necessary and look for a chance to run away from this forced union.
Sakura might initially be shocked and resistant. She is a strong - willed character, so she could try to fight back or find a way to escape this forced situation. Maybe she would first confront Sasuke about his unacceptable behavior.
In some fanfictions, Sakura's reaction could be more complex. She might be hurt not just physically but also emotionally. This could lead her to question her relationship with Sasuke and might cause her to make some big decisions, like whether to continue trying to reach out to him or to cut him off completely.
In some fanfictions, Sakura may be determined to find Sasuke and bring him back. She could set out on her own journey, facing various challenges along the way, and growing both as a person and as a ninja in the process of trying to reunite with him.
Sakura might initially be a bit annoyed by Sasuke's possessiveness. She's a strong - willed woman, after all. But she also understands that it comes from his love for her and the baby. So, she may tolerate it to some extent.
Naruto might initially be in denial. He's so used to having Sakura around and believing that they have a future together. So when she leaves for Sasuke, he might think it's just a temporary thing or that she's been influenced by something or someone. But as time passes and he realizes it's real, he would be deeply hurt. He might also start to question his own self - worth, thinking that he wasn't good enough for Sakura. And he might even try to win her back at first, but then slowly come to accept the situation and focus on his other responsibilities like being a ninja and protecting the village.
He might be initially confused. Sasuke is not used to Sakura ignoring him as she has always been somewhat persistent in her attention towards him. So, he may be at a loss as to why she is suddenly acting this way.
Sakura could also try to stand up for herself. If she believes that Sasuke is being unfair in his anger, she may argue back. For instance, if Sasuke is angry because of a misunderstanding, Sakura might try to clarify the situation and prove her point.
She may initially be angry. Sakura is a proud and strong character. She could confront Sasuke and Ino, demanding an explanation. After that, she might decide to become even stronger, both in her ninja skills and her emotional resilience, to show Sasuke what he's missing.
Sakura might be heartbroken. She's been in love with Sasuke for so long. She could initially go into denial, thinking it's just a temporary thing. Then she might get angry and vow to prove herself to Sasuke, perhaps by becoming an even stronger ninja.
She could be heartbroken. Sakura has always loved Sasuke deeply, so his leaving for Naruto would be a huge blow to her. She might initially be in denial, not believing that Sasuke would choose Naruto over her.
Sakura would probably be initially shocked and angry. She has always cared about Sasuke, and this betrayal would hit her hard. But she is also a strong - willed ninja. So, she would quickly gather her wits and start looking for ways to escape. She might try to use her knowledge of Sasuke's fighting style against him if she gets the chance.