There could be three possible reasons behind the everlasting dispute between India and Pak. The reasons being lack of governmental measures, global terrorism and strong influence of military in Pak's politics.
Though India has actively concerned about the Kashmir issue but from Pak point of view it does not look like they want to solve this problem far to easily, they are trying to sustain this dispute as of now this matter has lifted its base from a mere land dispute to matter of respect and ego for both the countries.
Active participation of militant groups and global terrorism groups in Kasmir valley in deviating and misdirecting the people out there in the name of religion and other sensitive aspects has also been a hinderance in the solution of the dispute.
The politics of Pakistan has a large influence from Military and the last two wars we have fought with Pak has been when Pakistan was under Military rule.
A peaceful solution can be drawn from what looks like a global problem the "Kashmir" issue only when we tackle these three obstacles at a same time.