However atrocious our government is, it pales in comparison to the actions of the British.
You have brothers against brothers all to the benefit of them.
The British definitely deserve a lot of the blame, but the guys in the OP deserve just as much of it.
Gandhi was an enormously unifying figure with stans across all religious lines and he wanted the subcontinent to stay together. A huge factor that kept that from happening was that these nationalists were so terrifying the Muslims that many Muslims felt there'd be no place for them in a Hindu-majority nation. If the Hindu nationalists had stood down and agreed to Gandhi's vision of a shared nation where everyone had a voice and you couldn't force your beliefs on other groups, India would probably still be together.
(It's possible Jinnah deserves some of the blame too, I've heard too many conflicting accounts of his role in it to really judge that for certain.)