Paki nuclear doctrine calls of nuclear response to nearly everything.
Read this.
en.m.wikipedia.org
They seriously think their nuclear cover gives them freedom to do anything and they can use nukes in response to any contingency.
Unless we can successfully call their bluff here or develop techs to negate their nuclear arsenal or convince them that they will suffer more in a nuclear exchange, this won't change.
This is why I call the blunder of not punishing pak for acquiring nukes one of the near irreversible blunders by independent India.