I second this.
Take some time to think things through, have a chat with her about it and if she's still upsupportive then start to think about breaking the friendship.
She may just be missing you. Some people lash out when they're hurt someone is leaving, it makes things easier for them. She could be doing this.
That's what I went through with a friend/writing partner. She couldn't have been more excited or supportive when I told her what I was going to do, but as it came closer and closer to happening, she became nearly bi-polar to the point I didn't know who I was dealing with one day to the next - one day, supportive and excited for me, the next - snapped at me and said really nasty things.
Only time I've heard from her since the move (about 18 months now) is when she sent me an email saying that her "women's group has told me I should forgive you for what you've done to me, so I forgive you."
Apparently she "quit the business because of" me... she also lives across the building from my former roommate whom I stay with at Christmas, and last time
she would not even answer the door when I went to talk to her.
So, as they've said above, I'm trying to keep it open if she ever decides to... lighten up and get over it... and I need to let go of my own resentment that she didn't support me through the biggest change of my life when I needed her.
You just gotta do what you gotta do, and hope the good ones will stick with you.
All my other friends from back home are in regular contact with me, and even some I've grown 'closer' to through email and telephone calls... so you never know.