The imaginary boy takes the hose fittings

We had another weird incident last night. Mum rang me around 6.30pm and told me a little boy who lives in the street had come in and stolen all her hose fittings and she couldn't water the garden. I asked if she saw him do it and she said "No, he did it when we went out." I said, "I never saw that little boy near your place."
She said "He was sitting on my steps when we left." I said "But I would never have taken you out in the car leaving that little boy on your steps! I would have told him to go!"

IT IS NO USE ARGUING WITH HER. SHE IS SURE SHE IS RIGHT. When will I learn to just shut up?

She started shouting at me and telling me I always try to make out she is mad and imagining things.

So I went over to see to the hose fittings only to find her attaching fittings TO THE OTHER END OF THE HOSE, THE END WHERE THE WATER COMES OUT, while the hose fittings were STILL ON THE OPPOSITE END OF THE HOSE, so now she has 4 hose fittings, on either ends of the hoses, and I was not going to argue with her any more.

I tried pulling off the fittings on the other end but they were stuck so fast that neither I nor the little boy could possibly budge them without some implement to help.

I turned on the hoses and they both still worked, with the water coming out of the end that's meant to be attached to the tap.

She hasn't stopped being angry with me ever since, that I didn't see the little boy on the steps, or I deliberately denied seeing him to make her look bad. She suspects I'm trying to have her locked up, and she refuses to go into hospital the week after next because she thinks it's all part of my plan.