Doesn't a B-12 deficiency affect mental health too?
I was reading the posting on this forum in response to my own ED problems when I saw your post.
I had stomach surgery on 8/13/04 and again on 5/02/05 to remove a malignant tumor and surrounding tissues. I also had Gleevec treatments from 11/24/04 until 5/2/05. I am fortunate to still have 30% of my stomach, but it was a full year before I felt anywhere close to normal and only after 18 months that my energy levels returned to normal. Right after the second surgery, the Dr. told me I'd need monthly B12 shots. I am scheduled to get a shot every month on the 12th. When I am late for the shot my energy levels fall off quite severely! I find myself taking an afternoon nap, even though I have a sedentary occupation (accountant & computer tech).
My ED troubles predate my stomach troubles by about 19 months. I have seen quite a bit of improvement in the ED problem over the last 6 months. The improvements started between 24 and 30 months after I started taking B12 shots. I still can't maintain an erection, but I am waking to more frequent nocturnal erections and have even had erections from normal visual stimulations. I still can't maintain an erection, but I AM having them. My point is that my ED problems have diminished since I started taking B12 shots. I doubt that the B12 shots cause the ED problems. I suspect that they may even have a therapeutic impact.
Not a professional opinion. Just my $.02.
Good Luck.