nhwife,
I have been on MDV3100 since December 2011, fatigue is certainly an issue. But fatigue is also an issue with Zoladex.
I am still on Zoladex, I would not call the fatigue "extreme", the fatigue from MDV3100 for me is not much worse than when I was just on Zoladex. I have odd days when I am more fatigued. Some of the fatigue is due to poor sleeping, I find that I don't sleep particularily well and I am awake at all hours of the morning. I have no trouble going to sleep in front of of the TV at 9pm, much to my wife's displeasure.
I do have to take into account I still work full time, 10 hours per day 5 days per week and I am 68. I am not as young as I used to be. (My mind probably is younger but my body is not !).
As far as I am concerned the fatigue, headaches and diarrhoea are well worth the outcome of the MDV. I am getting fantastic results from MDV.
The diarrhoea and headaches are definately getting less frequent, in fact in September I didn't have any bouts of diarhoea. Hopefully this means my body is tolerating the MDV better and not the MDV ceasing to work. Time will tell.
The only way I can get a good night's sleep is with sleeping tablets. I rarely use them because of the multitude of other medication I take for my blood pressure.
Good luck.