We are not ignoring our Mother tongue, as long as we can speak fluently in that language. But we can't talk to all the people in our Mother tounge. English being an international language accepted by all the countries, not only India, helps people everywhere to communicate with each other.
My mother tongue is Malayalam but how many ISC members will understand if I speak to them in Malayalam? There is no common language used in India, but internationally there is a common language. Hence we all learned English and is communicating in English.
By just knowing your mother tongue, you will be isolated in this world. We need to learn other commonly used languages as well to survive. Even after getting freedom we speak English so does the next generation. All the countries in the world was not under British rule, but almost everyone speaks English.
If you come to Kerala, it would be better if you can speak Malayalam, not that Keralities don't speak English. Knowing the language helps to you communicate with anyone in the state. Similarly when a Keralite visits Mumbai, he can't be adament that he will speak only Malayalam. Most of the people in Mumbai speaks Hindi, not that there are no people who knows Malayalam. It is better to know the language of a state if we are staying there. Knowing any language is an advantage only and we shouldn't feel ashamed of it.
"Do not give up, things might not favour you always"