Well, 'begin again' in a Twilight fanfiction could be about a character getting a second chance at something. Maybe a vampire getting a new start in the vampire - human relations in the Twilight world. It could also be a love story where a couple, perhaps Bella and Edward or another pair, start their relationship anew after some conflict or misunderstanding.
It could be Bella and Edward. Since they are the central characters in the Twilight series, it's very likely that in a fanfiction titled 'begin again', their relationship might be the focus. They could be starting their relationship over after some big event or change in the fan - created story.
A group of friends who had a big fight and drifted apart could be the main characters. In the 'begin again again fanfic', they are brought back together by some unexpected event and have to start their friendship anew. They have to face their past issues and learn to trust each other again.
I'm not sure specifically as I haven't read this novel yet. But generally, it might be about a character starting anew in life, perhaps after a difficult situation like a breakup, job loss or some personal trauma.
I have no definite answer. It's possible that it has some roots in reality, but it could also be entirely fictional. You'd have to look into the background and production details to find out for sure.
Alice's brother, Jasper, is also often overlooked. His backstory as a Confederate soldier turned vampire is full of potential for fanfiction. Writers could delve into his struggle with his past and how it affects his relationships in the present. Maybe a fanfic could show him trying to make amends for his actions during the Civil War in some way within the Twilight universe.
Well, it's also about the characters. The characters in Twilight are so iconic that fans can't get enough of them. In 'breathe again twilight fanfiction', fans can create scenarios that they wished had happened in the original story. For example, they can give a character more development or put two characters together in a relationship that was not explored in the original. This ability to play with the existing elements of the story makes it very appealing to fans.
One idea could be that the characters find themselves in a time loop where they have to 'begin again' multiple times in different scenarios. For example, they might relive a day but with different challenges each time.