If we're feeling flat, emotional, doubtful, mentally strained, worried, or physically tired for whatever reason, we can be vulnerable to the energy advances of others. This is why it's so important each day to keep your energy field looked after, high and as bright as possible.

HOW TO LOOK AFTER YOURSELF AND PREVENT PSYCHIC ATTACK / LOW ENERGY

• Eat good healthy fruits, vegetables and wholesome food.
• Exercise every single day. Keep your body strong and full of light.
• Drink lots of fresh water and meditate regularly.
• Make sure that you go to bed at a reasonable time to receive ample sleep recovery.
• Do your best not to fixate on social media or putting all of your energy into the IDEAL or illusion of someone else.
• If someone is bothering you online (with constant messages or energy stalking) then don't hesitate to ban and delete them and as you do so, ask that their energy be sent back to them. Even if they're being sickly sweet, it can be just as bad as someone who is directly rude to you. You wouldn't allow someone to come up to your house and write graffiti all over it without taking action to look after yourself. Your online presence is the same. Be strong and direct in your approach.
• Regularly open your windows and smudge or clean your home, body, work space and online presence.
• Do your best to occupy your mind with what makes you feel good, laugh and focus on your heart chakra. A strong heart field is the best tool against any type of psychic attack that comes your way.

SIGNS THAT YOU COULD BE RECEIVING PSYCHIC ATTACK

• You could feel flat, drained, tired and emotional for no good reason and while you feel this way, a certain person keeps popping into your mind. You're thinking of them constantly. It's like they won't leave you alone.
  
• You may know this person who keeps popping up in your mind or you may not know them. Either way you can feel that someone has directed heavy energy - your way.
  
• If you answer, Yes, to any of the above you may also notice that your projects can't quite get off the ground. Every time you start something new, it goes wrong or there are setbacks. No matter how positive you try to feel or how fresh you desire to begin each day, there is a cloud that follows you around. And when you think about this, you get the feeling that a certain person is inside your head, gossiping about you or sending you negative vibrations.
  
• NOTE: some psychic attack is quite sneaky in that the person sending the low vibration may act like they're your best friend or admirer to your face - and particularly ONLINE. But, you feel that their energy is not sincere and they drain you. This type of attack can be more difficult to identify and it can linger longer than someone who is more overt in their feelings towards you.
  

Source: https://elizabethperu.com/blog/psychic-attack-aka-the-illusion-of-others