Hi Craggyva,
My English is not very good so please excuse my writing. I wish I knew what to say about the situation you describe but sadly I lack wisdom. I don't know, but I would imagine that others who are nearing 50 . . . other men from all over the world have experienced something similar to what you describe.
The human brain is so mysterious and sometimes seem to have a mind of its own. Sometimes when someone is troubled by what their brain is doing, it can help to talk to a professional therapist. Don't know if that would be appropriate or help in your situation but perhaps it is something at least to consider.
So sorry that I lack insight. Hopefully others here on the Forums will make up for my lack of wisdom in this matter by offering their own ideas.
I wish you only good things! -- Yaowen