Well to be honest, I'm not surprised that her co-workers and family knew first.
Co-workers because she went into labour while at work - so that's probably gonna spread like wildfire in the office. My co-workers knew before many of my friends because I was admitted into the hospital on Friday morning when I went into labour 2 weeks early. We had to tell my boss that I wasn't coming back! My colleagues sent out a mass email telling everyone to divert all traffic (work and emails) from me to everyone else XD
Family had to know since we were supposed to be having dinner with my in-laws on Friday evening and obviously that had to be cancelled. And since we had to tell my in laws, we had to call my parents too.
Friends found out when I Facebook-ed from inside my delivery suite. Well, it was a LONG 24 hour labour. I even watched the World Cup quarter finals until the contractions got too bad. Fun stuff.
Anyway, just to say this: it could be any number of things that caused your friend to turn away from you. Difficult pregnancy, raging hormones or simply just a really bad friend. Let things slide. If she was always like this before the pregnancy, then it's probably the latter. Otherwise, if she returns to "normal" someday (typically 2-3 months after the birth of the baby), I do hope she will apologize for her "craziness" and that you will welcome her back into your fold.
I have to admit, I will probably be very forgiving towards your friend. This is because I experienced a fairly difficult pregnancy whereby I needed to undergo a surgery in my first trimester and risk a miscarriage (or refuse the surgery and risk losing the baby + damage my uterus). No one knew about it except for very close friends and immediate family. Also, my baby almost died at birth. We didn't share that with anyone except for the immediate circle for at least 6 months. I am now comfortable with talking about it, but during that time I practically secluded myself. Oh yeah, and I had pretty severe PPD and was acting CRAZY for at least 2 months (and crying every night). I figured that it was better to seclude myself than to say horrible things and hurt people. My hormones stabilised about 2 months after the birth of Angel, and I started calling up friends again. I barely explained myself, only to say that I wasn't ready and it was a hormonal time for me. I'm lucky that most of them understood.