Thank you for the replies to the questions and the added information. It helps a lot in understanding what the situation is. I believe I can now be of help with this issue.
I can imagine how embarrassing this situation must be for you. You are clearly a loving and caring son and a good brother. And this is a very abnormal situation. You have two choices here. One is to do nothing and the other is to get involved.
I don't know how to tell you which one to decide. Because this is very embarrassing and they are both adults. And you have the right to live your life. So if you choose to do nothing, you would need to continue to encourage your mother to take action by telling your brother to seek help. And that she can offer to go to a psychologist or psychiatrist with your brother to help him. But that is it. And then don't get any more involved.
If you choose to get involved because you are worried for your mother, then you will need to become more embarrassed. This is difficult, but you need to ask your mother to show you the emails he has sent. If she says she destroyed them, then you have to tell her you need to see the next ones he sends. Why?
I said this will be difficult and it is: you have to verify that your mother is not having delusions, that the problem is really with your brother. Your mother is older and she may be having her own problems that may be causing delusionary thoughts or misunderstandings. So you need to verify first who is having the problem here. Okay?
Once the problem is identified, if it is your brother, then you need to ask to see him personally and ask him to let you go with him to a psychologist or a psychiatrist to talk about the situation. Offer to go with him so it is not so scary to him. And then he will be in their care and he can get help.
Okay, I wish you the very best!
My goal is for you to feel like you've gotten Great Service from me and the site. If we need to continue the discussion for that to happen, then please feel free to reply and we'll continue working on this. If the answer has given you the help you need, please remember to give a rating of 5 (Great Service) or 4 (Informative and helpful), or even 3 (Got the job done) button. This will make sure that I am credited for the answer and you are not charged anything more than the deposit you already made by pressing any of these buttons. Bonuses are always appreciated! If I can be of further help with any issue now or in the future, just put "For Dr. Mark" in the front of your new question, and I'll be the one to answer it. All the best, XXXXX XXXXX