Language Mixup

Afghanistan had been invaded by world powers of different historical times before and each invasion  had lefts its mark on the history and society of the country. My history information is not that great so I can't give specific examples but I am witnessing a historical change in the language and literature of Afghanistan at the turn of the century. Afghans speak Dari, an almost pure and very self sufficient language so far. Up until recently, our literature had borrowed very few words from other languages. But with mass migeration of afghan people to West (Europe and US), and new generations being born and raised there, a lot of foreign words, phrases and language is being integrated with the Dari language. It is for many reasons, whether the whole concept is new to our tradition for which we didn't have any words and phrases before, whether our own phrases are long or outdated and the youths are more comfortable with new language or it is because we have been away from our homeland and traditions long enough that our own language and traditions are starting to escape our lifestyle and are being replaced by new ways of living and communicating.
It is a bit of a challange to be bilingual and still be fluent in both languages in a pure and original form. I had a great grammar and vocabular knowledge of my mother tongue, not anymore. I am focusing more and more on being fluent in English since this is becoming my primary language of communication.
I have a 18 month old who is learning to talk. I wanted her to learn Dari first and be fluent in it from the start. But, I took her to play ground the other day and was kinda shocked to realize that my baby needs to learn English first and foremost. On the play ground, she wanted to play with other kids, she loves babies. but when she approached other kids, they didn't undrestand her words and her invitations to play. so they just walked away from her as if avoiding an alien. My daughter didn't care about it and she played here and there. But it was an eye opener for me. she needs English to be able to communicate with her peers. Although I will keep talking to her in Dari, I will try to teach her English in a formal setting and on a daily basis. I don't want my baby to have the kind of language barrier that I have.