Yes, sometimes they can. If the story has very unique details or a particular sequence of events, and you replay it in a way that's not natural or if you make the same mistakes again while re - telling, they might notice. Also, if they are very familiar with their own story and your re - telling seems too rehearsed or lacks the spontaneity of a first - time hearer, it could raise suspicion.
Well, it depends on the platform. Some apps or social media might give you a notification or show you stats that let you know if someone replayed your story. But others might not have that feature.
Maybe. If the person is not very attentive, they may not notice. But if they are sharp, they'll look at how the story is being used in the new context. If it seems like you're just shoehorning it in without much thought to how it relates, or if you're using it to make a point that doesn't really fit the new situation as well as it should, they could figure out that you're replaying their story. Also, if the story has some unique elements that are out of place in the new context, that's a sign.
Well, it depends on the platform. In general, not all platforms are transparent about whether someone has replayed your story. Some apps might keep track of it for their own internal data analysis but not show it to the user who posted the story. So, usually, it's not easy for an individual to know for sure if their story has been replayed.