I'm not sure about a specific one that stands out above all others. But generally, in such fanfictions, they often get to travel the world, discover hidden magical places that normal wizards could never reach in a normal lifespan. They might also use their immortality to protect the wizarding world from threats that surface over centuries. You can search on fanfiction platforms using keywords like 'Harry and Ginny are immortal' to find some interesting ones.
Ginny might support Harry by simply being there for him. In the face of everyone else turning their backs, her presence can be a great comfort. For example, she could sit with him at meals when no one else will.
One possible reason could be miscommunication. Maybe Ginny feels neglected by Harry because he's so caught up in his own heroic deeds and doesn't pay enough attention to her. So she might seek comfort or excitement elsewhere.
There could be many interesting fanfictions on this topic. One idea could be that in this fanfiction, the 'force' might be some sort of magical or emotional force that binds Harry and Ginny even closer during her pregnancy. It could explore how they deal with the impending arrival of their baby while also facing challenges related to this special force.
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.
Definitely not. The 'Harry Potter' franchise has a certain set of values and themes. Fanfiction of this sort goes against those values. It's not respectful to the original story, the characters, and the fans who expect a more positive and clean representation of the Potterverse.
Definitely not. The 'Harry Potter' series has always been about good triumphing over evil, and the relationships between characters are built on mutual respect and understanding. Enslaving a character, especially in the context of Harry and Ginny, is a very wrong and inappropriate concept that doesn't fit with the overall positive tone of the series.
A popular one is 'Harry and Ginny: The Next Generation'. It's an interesting take as it focuses on their life as parents and how they pass on their values to their children. It has a great balance of family drama and the magic we love from the Harry Potter world.