In his case I think "you already told me that" originally was meant to do me a favor, relieve me from having to expend the energy to tell him something. And do him a favor -- spare him the 19 seconds of life he is about to lose to getting information he already has.
He would jump in so fast and adamantly when he he thought I was going to repeat a story that I interpreted it as:
"you are so boring it's painful. I'm in a total panic to stop you from talking." (but I swear to God I had only said one sentence so far.)
I told him that he was not helping me. What I got out of it was feeling close to him. He talked over that too, but he must have heard because he really has stopped reacting so strongly. Now I will say "stop me if I told you this before" because I'm really self conscious about boring him, but I realize just now, he hasn't had a panic attack over me repeating something for months.
Oh my God -- maybe he really DID think he was doing me a favor.
He is very efficient and constantly looking for ways to cut steps. For example it drives him crazy if I peel carrots over the sink, then place peelings in trash when I could have just peeled them over the trash.
PS - the conversation you described with Batman is kind of what I'm looking for and I promised myself I'd go for a guy who liked discussing ideas and things. But he is not that guy. But he checks off all the other boxes and I do have other friends and family I can philosophize with. I don't have to interpret it as he doesn't like my personality.
It isn’t that you are boring him. I don’t like being told something twice as if I am a child and need to be reminded.
I actually think my wife is forgetting that she has told me things 3 or 4 times already. She will go over some things as if it was for the first time.