Which teenager vampire romance novel is this?

The beginning of the book was that it was in the 1700s-1800s and a guy was trying to leave but the girl didn't want him to but he explained to the reader that this happened everytime they came together. then it takes you into the present where a girl goes to this academy and lives there and such. Well, there's a boy there that looks at her strange and tries to get away from here but they wind up getting together. Long story short it turns out that the boy is a vampire and the girl keeps getting reincarnated. Every time she does they find each other again. It ended in a jealous vampire trying to kill the girl b/c she loved the boy but they had like a battle of her then it ends with him putting her by a lake an saying he'll come back to get her. I was wondering if someone knew this becuase i would really love to know what its called