You have told them stories about yourself but when you're talking to them they seem absent-minded and after a few days when you tell the same story, they react as if it was the first time they've heard it. Not paying much attention when you're speaking to them is a disinterest on their part. But what are they thinking about when you tell them these stories? Maybe physically they are present with you at the moment but in their thoughts, they are intently thinking about another person.
Absentmindedness is a symptom of a possible cheating. Their eyes are far off fantasizing about having intimate moments with someone else. Even if they haven't committed the act, the emotional cheating is just as bad. Sharing stories is important for a relationship and if you don't appreciate your partner's stories then you're not appreciating them as a person.