Lisa Renee, who is an awesome source of good information on the dark side and defending against the dark side, has a short free online course that she's put up on her website. She has more you can buy at a nominal cost.
This one session talks about free floating negative thought forms and how they can attach and attack, yes, your energy body. When you're around others who are putting out negative thought forms, either generally or targeting you, they can attach to your energy body and drain you.
I clear often, pulling white light through my energy body, rebalancing the chakras and cutting cords (which is another source of potential negative energy).
When we love bomb, I ground, pull in energy through my feet and open my crown, pulling in clearing energy through that chakra. I don't shield but I have a good video I can put up to teach you how to do this.
Renee recommends the 12 dimensional shielding process. I haven't done that. Anyone do it that can help out here?
Yes, just like there are flu viruses and cold viruses free floating in the air to make your physical body ill, there are negative thought forms and entities free floating to make your light body sick. And you'll feel it because your energy gets low. So either do maintenance on a regular basis as a preventative (preferrable) or do it when energy is low.
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