1. We are Muslims and will remain Muslims.
Islam in Bangladesh is amongst the oldest in the world older than Indonesia, Pakistan, Morocco (maybe even Egypt) due to Said bin Abi Waqqas, a companion of the prophet coming to the area (radi'Allahu anhu).
2. Nepal is Hindu but despite having the same religion does not merge with India.
3. India would never want to annex Bangladesh as it has 150 million Muslims, dealing with Kashmir and Naxalites is bad enough but add 150 million Muslims who have vivid memories of statehood then that is a recipe for disaster.
4. Do not understimate the importance of merely having your own state on the consciousness of a people. The Kuwaitis have their own flag, army, anthem and they would never accept being annexed by fellow Arab Muslims in Saudi or Iraq.
5. There are religious groups that are indifferent or supportive of the Awami League e.g. Deobandis, Tableeghis, Fultolis who outnumber the Jamatis by far.
Some of these groups are also quite anti-Jamati.
Islam in Bangladesh does not equal Jamat or Maudoodism.
This is a gross overreaction to the whole issue.
Bangladesh is here to stay and going nowhere.
Jamatis on the other hand (despite what they say) ultimately want to destroy Bangladesh, i.e. its existence as a separate independent nation. The older leaders of Jamat have vivid memories of Pakistan days and nostalgia for it and believe it is a religious duty to be part of Pakistan. The younger members are not as Pakistano-philic but ultimately believe in a confederacy at least.
So it is Bangladeshi nationalists who are striving for an independent Bangladesh whilst Jamatis are striving for the end of an independent Bangladesh.