Time travel and love, Uuuhf¡

Hi, dear students. I expect you are having a very nice weekend.

Well, let’s do the homework. As I told you in class you have to investigate the title of a book, the name of the author, the publishing house, the city and the year.
Of course, you have to send me this information in the correct order of a bibliographical reference.

A very good friend told me he read a novel. He said the novel was excellent and he recommended me to read it.
I don’t remember the author. I don’t remember the title, either, but I remember the story:


It is about a man with a genetic disorder. This disorder does not exist in reality, only in the novel.
So what happens to this man is that he travels in time involuntarily: from present to past, from past to present, and from present to future.
Since this is a science fiction story time traveling is possible. But this is also a love story. And in love stories you have a counterpart, in this case a woman. The woman is the wife of the time traveler.
The time traveler goes back to her past a number of times, to her infancy and adolescence. In one of these visits he tells her they will get married in the future (the future is the present from where he begins his travels). When she is 20 years old and he is 40 years old they get married. He also travels to the future. His last travel to the future causes his death. He returns to the present just in time to die in the arms of his beloved wife.

But that is not all: the devastated wife discovers a letter from his husband in which he describes an encounter they will have when she is an old woman.
So she will see him again one more time.

Could you help me find out what novel is this?

Thank you!