Iran had to side with India coz Pakistan keeps acting like a vassal state of Arabs.
I'm a Sunni and and even I know since childhood that we have been bad neighbours to Iran. There are enough examples of what Pakistan has been doing to Iran too.
Secondly, we want all the share of oilfields in Baluchistan despite the larger part of reservoirs being in Iran. The result ? Neither Iran, nor Pakistan has been able to extract oil for the last 50 years.
Whereas look at Qatar, they shared the gas fields with Iran, explored them together and became the richest country in the world and today we go to the same Qatar for financial support.
Unless we start acting sensibly and bring a balance between our support for Arabs and our relations with Iran and make similar deal like Qatar has done instead of wanting all the oil, we cannot expect Iran to just go with us. I believe we have been more hostile to Iran than they have been to us. We have to take the steps to become better neighbours to them too, if we expect a change in their acts.