It's sad to hear. Unfortunately she probably has moved past everything, and you've internalised it. She was never really a good friend to you anyway. You shared some memories but thats all, maybe they exist in your mind but not hers. It's just anxiety now, these feelings. I feel like you could take the risk and ask her why she just disappeared but go in with the thought that she doesn't owe you anything, or just focus on yourself and move forward, appreciate the memories and move forward my guy - the latter is better, if you can do this more in life, the problems resolve themself, it's a real lesson some of us should've learned earlier. I'm not even good at that yet. First step is realising, the next you decide.