N-Father

My n-father is incapable of following a normal conversation. Here is an example from a conversation we had tonight:

Me: I had to get some blood work done yesterday. They mixed the tests up and mine said I needed to get my iron levels checked for anemia.
Him: What is anemia?
Me: Well, in this case, it's iron deficiency anemia. Basically, it means the body isn't getting enough iron. We think....
Him: (interrupting) I was eating chinese today and do you know what my fortune cookie said?
Me: Um, what?
Him: You will soon go on a trip and gain wealth.
Me: Ok.

Later, I was talking about eliminating things in our diet to help with my husband's anemia.
Him: Couldn't he just try doing water aerobics?
Me: (in a very confused voice) To fix the anemia?
Him: No, to raise his metabolism.

I was too confused at this point, so I let him go on with whatever flew into his head (like I usually do). Most conversations consist of me saying "uh huh" and laughing whenever appropriate. He does all the talking. As you can see from above, there's just no point in trying to have a normal conversation. He lives in his own little world and that's what he talks about.