So how does one cure this complex as you have described it?
The way I see it, and you might not agree, but there are two ways of curing this complex.
One let's invade India, kill or convert Hindus until they become a small minority in the sub-continent. Because for me one of the biggest reason for this complex is wish of Muslim of Sub-continent in general and Pakistan in particular to keep their identity as a separate people. Think about it, if the Coptics were still in majority in Egypt or if the Egypt had a strong Coptic country as its neighbor and rival with a bitter history , do you think the Muslim Egyptians would be this proud of their shared heritage? I think they won't be.
But it is not only preposterous to think about such an eventuality, but it is also impossible to achieve. If we were not able to achieve it during the hundreds of years of rule over Hindus, it is not possible now. Of course in a 100 or 200 year from now Muslim might be in majority in Sub-Continent but that is another story.
Second way is to make peace with India, not only peace but an alliance and friendship that will put US-UK or US-Canada relationship to shame. Once our people and establishment become friendly towards Hindu-majority India, we will not need this urge to keep ourselves distanced from our shared heritage.
This is not something that can be archived either. First it does not only depend upon us but also the Indians to achieve such a relationship. And they won't agree to it until we accept them as big brother in the region, the regional hegemon and that is not something that is acceptable to us (myself included).
Third and the only possible solution is to change the bloody curriculum and start teaching our kids about MehrGarh, the 9000 year old civilization. Tell them about Harapa and Mohinjodaro, not the casual manner that we do right now but in detail and show to them why it was unique and how well planned and managed cities they were as compared to their contemporaries in say golden crescent.
Tell them about Takshila university of antiquity, and how it was a center of excellence when most of human race was still living in caves and tents. Tell them how valiantly people of this region fought against invading Macedonians, make people like Porus of Jehlum their hero, tell them how Alexander nearly died while trying to conquer Multan.
For Punjabis for example, portray Dhulla Bhatti as a freedom fighter against Mughals, he was pretty much the Khushal Khan Khattak of Punjabis but how many Punjabis actually know his history. And yes make Khushal khan khattak part of the curriculum too.
If the kids keep on listening only about how awesome bin Qasim or Ghaznavi were, they will keep idealizing them. Hence they won't be able to relate to their own land and always look outwards for a sense of belonging.