She is asking if he has left her, how he is, if I have seen him, when was the last time I saw him, etc. I've told her a couple of times telling her that he has passed on, but this seems cruel since it is new to her each time. Lately it seems equally cruel to have her thinking that he is ignoring her. Redirecting has worked some, but today she was quite persistent. What to do?
Find what answers would be appropriate to give your mom some comfort. This could be just a phase and it will pass.
Unfortunately, mom now has forgot about dad. I show her old black and white photos of them together from time to time. She knows who he is occasionally but the association that he was her husband is no longer there. After 43yrs of marriage her only memories is that when they were teenagers. For me that is so difficult to understand how you can forget a man you were with for so many years.
Don't feel bad about lying to her. Your just saving her from the grief and pain. Let her enjoy good memories even if they last a short time.
What a very difficult spot you are in. Congratulations on trying to work out the kindest way to handle it.