Why did she suddenly stop talking to me, What happened? Please Help!!!!!?

[kicks]

In my opinion, girls can be ridiculous. I know from experience considering I am a girl and have put up with a lot of stupid crap from others. I have watched girls use guys and start to ignore them for no reason, so I think to start off you should lay low for a while.
Then, after letting her be for a while, you should ask her whats up or just say hey and see what happens. If she continues to ignore you, then maybe it is time to move on, she is clearly not interested. For what reason? Who knows, she is a chick; girls do weird stuff without cause. If you really want to continue talking to her, simply ask her why she is ignoring you.
If you get a response, don't ask so many questions and keep things casual. Leave it up to her to make it anything more if she would like.
I suggest finding some other people that you have things in common with to talk to in the meantime. You said that she has a child, so that is probably a big priority in her life and she may be worried about getting to involved, especially with someone so far away.
Hope that I helped.