Sounds like a good time to detach from the whole situAtion. You can still care about your friend without losing energy to her problems. If you are getting ill from her stuff it's a pretty good sign that you may be too invested in something that is ultimately none of your business. I know that letting go of good friends issues is really tough. As a friend we think we should be there to help and support, but there comes a point when it's good to step back, realize they are adults a fully capable of making their own (bad)'decisions, and that you have zero control over it. I've been know to set a boundary- an example might be, I really care about you, but I find this very upsetting and I need to not listen to any of it anymore, as in " not a topic for discussion ever" kind of thing. That may be one way to keep your sanity.
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