You talk about how those fighting in Kashmir against India are martyrs, of how all Muslims in Jammu and Kashmir want to join Pakistan, of how Muslim Kashmir [Jammu Has More Hindus] should've become part of Pakistan. Basically, your entire claim over Kashmir is based on Islam and all those fighting for liberation of Kashmir are fighting for Islam.
Now since you decided to bring religion into this, have you ever thought over what the Holy Prophet PBUH and the Quran has said about those that break Treaties and Promises. And by bringing in UN every single time to discuss Kashmir, Pakistan is violating the terms of the Simla Agreement.
India returned 90,000 POWs and 13,000 km2 to Pakistan after the 1971 war [In the Simla Agreement] and in return, the Kashmir Issue would become one only between Pakistan and India, no Third Party which includes UN or whoever tries to poke their nose in. The agreement even explicitly mentions
(ii) In Jammu and Kashmir, the line of control resulting from the ceasefire of December 17, 1971, shall be respected by both sides without prejudice to the recognized position of either side. Neither side shall seek to alter it unilaterally, irrespective of mutual differences and legal interpretations. Both sides further undertake to refrain from the threat or the use of force in violation of this line.
Which literally means that Pakistan shouldn't even be thinking of plans to occupy Kashmir.