Testosterone is a hormone, that well, for the most part, makes a man a man. In the case that you are a female transitioning to the male sex, testosterone boosters may be of much help to you. I absolutely cannot imagine the internal struggle a transgendered person must go through. Knowing that your outside does not match who you are on the inside.
I don’t normally watch The Real World (on MTV) anymore because it’s become super lame, but a few seasons ago they had a female who had completed her sexual reassignment. I did watch that season because it was just insane to me, to see this person struggle with something not many other people do.