Says he wants to see us together so he knows. This happens in the evenings. His Mum died many years ago. He is amazed I can use a mobile phone & computer and asks who taught me. The other eve he asked if I was staying the night & said there was a spare bed in the other bedroom! Sometimes feels quite weird!
You probably won't be able to convince him that you are not his Mom so can you just play along with it? That's what I'm trying do when my husband is convinced of something that is not true. Of course, there are some things that I can't agree with but when I do tell him what's really happening he thinks I'm lying. I have learned that you can't win. I also remind myself on a regular basis that he can't help himself.
How long have you been dealing with this?