Depression and short term memory loss were the worse aspects for me. I couldn't remember what I had seen on TV the night before. The hot flashes were miserable, cost me a lot of sleep. It all interacts: tired, no energy, lost sleep, a hot flash when you least expect it (is it hot in here or is it me -AGAIN?) = a depressed state . Some days I felt like walking in front of a bus. There's also this pissiness. My wife had gone through menopause a couple of years earlier, so I did get a lot of sympathy, plus a lot of "Now you know what it's like" gloating.
The libido aspect is kind of strange: It's true that you have no desire, but I got my Lupron pre-RP, so I had no erectile issues. Once I got started (with sex initiated by an exasperated wife) I had no performance problem and a normal erection and orgasm. It's not that you CAN'T do it, it's just you couldn't care less. I ddin't get any CASODEX moderation, so I had the testosterone flare, lasted about a week. Whoo! Whoo!. I went from wanting sex all the time, to absolutely no interest whatsoever, all in about a month. Interesting period in my life. Don't want to do it again.
I understand from reading that the side effects moderate after a while, but I only got the one 4 month depot shot June2008). I didn't recover from it until I got testosterone replacement therapy (Andorderm patch) in Jan 2009. Robotic RP was Nov 23 so I was pushing the envelope a bit. One of the first things I noticed was that I was looking at the women in the supermarket again. Here's an interesting and encouraging link:
http://www.ustoowichita.org/pdf/MYPROSTATECANCERSTATS.pdf
I suspect that T replacement could be a very valuable addition to post-op erectile rehabilitation. I also suspect that you are not going to find a single urologist in the world who would adopt such a protocol -and with good reason.