When reviewing a book such as Nabokov's "Lolita", you must perform somewhat of a balancing act. This, of course, is due to the subject matter of pedophilia. If you could imagine such a balancing act performed on a simple review in 2008, could you imagine the balancing act performed as an author in 1955? From my point of view, Nabokov handles this balance very well while at the same time producing a story that is believable, gut-wrenching and even sympathetic.
The connection Nabokov creates with the reader is the main reason why this novel is a classic that has withstood the test of time. Nabokov makes you feel sympathy for his main character (Humbert Humbert) while at the same time feeling complete and utter disgust for such a gruesome man. These back and forth emotions that he creates within the reader leaves you exasperated and questioning all guidelines created by society. While the result of your struggle is "this is wrong", it is hard to define specific boundaries. Could you imagine being in charge of a government where you had to draw a line in the sand to determine when a child became an adult and when he/she could now be blamed in the eyes of the law? Should the line be the same for those "children" who kill people? When do they have the wherewithal to know the ramifications for their actions?
While a child may know that to hit someone creates pain and that a bullet can also cause pain, do they really have a concept on the difference between pain and death? At what age can they fathom the difference?
The truth is, it's different with every person. I think Nabokov's purpose for writing this novel is to make you think about the ramifications of drawing lines in the sand or painting anything with a broad brush. Sometimes it is necessary, but there will always be exceptions to the rule.
In the case of "Lolita", Humbert Humbert tries to persuade himself (and you) that the "relationship" COULD be viewed from many different angles. While he himself admits it is WRONG and DESPICABLE, he cannot curb his own desires... pedophilia is indeed a sickness.
Whether you abhor Nabokov for writing such a work or not is really up to you. My opinion is simply that Nabokov wrote a fascinating novel about a man's struggle with a sickness which elicits many different emotions within a reader and causes him to question where a line turns from white to black.
Note: I almost forgot to get into the prose!
The fact that Nabokov wrote this novel in English and not his native Russian (he is fluent in 4 languages), is impressive. His mastery of the English language is nothing short of remarkable. The constant desire to use french without explanations was a little distracting, but this point is a minor one. Nabokov is more of a descriptive writer than an emotional one, but his descriptions are absolutely beautiful. I prefer feeling to description (see Dostoevsky, Pasternak, Turgenev), but there is no denying the beauty contained within these pages.