Have you asked your social worker about getting some counseling? After all you've been through, how could you NOT be depressed?
When I first started dialysis, I went to counseling for about three years. The talking therapy was helpful, but they also decided I needed medication. I was on Zoloft for awhile-- it helped with the depression, but it had one bad side effect: I couldn't write anymore! (I need to be a little melancholy to do any serious writing, and when the Zoloft got rid of that, my writing ability went out the window!)
So when I told my nephrologist that I was going to quit taking Zoloft, he said that not being able to write wasn't a 'big deal.' Well, SCREW HIM! Dialysis has taken away almost everything I enjoy-- it wasn't going to take my writing, too! It took about three months for my writing ability to come back, and in fact writing has been more therapeutic than the drug-- I post my dialysis-related stories online and people comment on them.
I had the same short temper you describe, but I had it while I had my transplant. The prednisone made me psychotic, and I always felt one step away from punching people in the face. This was very scary for me, because I was very timid as a kid, and never stood up for myself-- I was like an entirely different person when I had that kidney, and it was hell.
The transplant doctors swore up and down that my personality would return to normal once I got the prednisone out of my system... well, it's been 13 years, and I still am more aggressive, my voice changed, and I still have the male-pattern hair growth that they claimed would go away! That's why I took my name off of the transplant list-- I can't trust a damned thing they say. You're a male, so the male-hormone effects of prednisone probably weren't noticeable, but in a female, they're life-altering!