Richard, welcome to the forum. I am two years post brachy. I started enjoying sex again
two weeks after my procedure. Everything feels the same without any changes. I do have some ejaculate loss (maybe half) but that does not change the feeling at all.
I have heard that some brachytherapy patients experience more ejaculate loss than I have but I don't recall that subject being discussed on this forum. We have a number of brachy patients who post here fairly regularly. Hopefully some of them will weigh in with their experience on this.
Best of luck with your procedure. If you want to see what is was like for me, please feel free to check out my journey via the copy and paste link in my signature.
Tudpock (Jim)