Nifong's behavior goes beyond crass opportunism, namely, his rejection of any exculpatory behavior, his ignoring of the lack of physical evidence and his refusal to adhere to what appears the norms governing interactions among DAs and defense attorneys. His initial grandstanding plays to your point about his political opportunism. However, more worrying is his denial of reality: AV's statement of no condoms (if true) and lab report of no Duke LAX DNA. Assuming he and his team are not complete morons, then we have to deduce that Nifong is trying to manipulate reality through his power, his denial of the obvious and his gross misrepresentations.
As to self-hating, I think the behavior is more likely to be narcissistic - self-loving - a la John Kerry.
I would definitely bet that not all the relevant items were handed over to the defense. Watch for a number of key missing items. I hope the defense has a good list of what should have been in that packet. I guess I am assuming that there is nothing damning in the evidence Nifong released to the defense.