I'd feel the same kiki2. It's like a bereavement and I don't think you should feel guilty for experiencing painful emotions. You are human and why wouldn't you be feeling like this? It won't be possible to put a positive spin on the situation while you still feel so stunned and raw, so I'd say don't even try. For the time being, accept your feelings, pain, sadness and all. Give yourself some loving compassion as you would to a friend going through the same thing. It would be perfectly OK for you to tell your friend that you will miss her a lot; that you will miss her company, your meetings and closeness. She will almost certainly have mixed feelings and sense of loss also.
I would agree that it's probably a better plan to see her if you can. You might send mixed messages otherwise, and meeting would give you both a chance to express some of your sadness. If you continue to avoid her you might regret that later and it could signal to her that you didn't value your friendship as much as she thought you did and she might make less effort to keep in touch or to respond to your messages. Take a deep breath and decide to make the most of your remaining time together. Treat yourself gently, take it slowly emotion-wise, but nurture all you have here and now. Good luck.