Rant sorry in advance!

My bestfriend of 12 YEARS up and deleted me off every social media, blocked my number and everything... LITERALLY FOR NO REASON. Our friends that we share will mention it to her and she says nothing. Im at a complete loss. I was there for her through everything. Her pregnancy at 15, all the surgeries her son went through, her 3 other pregnancies, PLUS clothed one of them (the youngest) when she couldnt even afford to do it herself. I have been by her side since we were 11, graduated grade school and highschool with her. Shes like my sister. Im at a loss of words to even understand how i feel. Its worse than a breakup ... shes now just a stranger who knows all my secrets. And i dont understand it. Maybe it hurts more because im pregnant but idk