At the risk of possibly sounding discouraging, Sanclaire, I do agree that the Nal can intensify the hangovers. I can definitely relate to the jittery feeling, coupled with the "kill me now" headache and nausea 

 Avoiding dehydration and making sure you have a bit of food in your stomach when you're drinking can help, and I believe your body should adjust to the medicine to some extent with time. 
And honestly, if anything, I feel the bad hangovers helped to played a part in breaking my former love affair with alcohol.  It may sound weird, but once I had begun to stamp out the endorphin reaction and could think more objectively and rationally about the decision to drink or not, I would consider the potential hangover and just decide to pass on some nights. 
I rarely get the killer hangovers anymore, which is probably due in part to my body adjusting, and partly from adapting my behavior - i.e. learning to stay hydrated, generally avoiding wine, and cutting back the amount of alcohol consumed in a sitting.  However after some of the hangovers I've had, drinking during the work week does not usually strike me as a great idea anymore, and in fact the thought makes me feel a little anxious/repulsed. 
And honestly, I couldn't be happier about it, which is kind of funny (well to me anyway)  
 "Hang" in there, buddy - pun intended!  You won't regret it for a second.