I'm sure many of us here have had someone attack us on the Metaphysical level, whether out of jealousy, misunderstanding, plain old hate..whatever the reason they are sending you bad Energy.
It can also spill into the "real world" with them trying to trip you up, lying about you to others, etc. In any case damned irritating. I have been dealing with this nonsense from a woman for over a year now.
I'm aware I am more Powerful than her, and in the past I would have thrown a whammy at her like no tomorrow, but I've learned over the years Karma doesn't care who started it and I would end up getting something bad in return. So I chose to seal my home against her crap and ignore her. This involved circling my property with Sage burning, and the intent to seal against any and all Evil. Then I left Dead Sea Salt across each doorway.
(You will find if you do this true friends will love the feeling in your home, and anyone who is not true to you will be very uncomfortable there)
She carried on in the physical world with lies, so I then added a bit of "bounce" to the walls around my property-only reflecting her own negative against her (but propelled by the bounce of the walls I have seen it likely gained Power).....this was done the same as the sealing but now the intent to reflect it back was added to my wall. I did this step mainly to save my Energy for a very tough healing I was involved with that needed my full attention, not this other nonsense.
This works very well IF you are truly in the right...you must look within at your part in the dispute and make sure you are not a part of the problem or even the cause...we can lie to ourselves and others but not to the Universe. I am convinced the Truth is the most powerful ally you can have in these matters.
I am trying to keep this short....the simple measures above were my part in the "war" she started. She tried her heart out on every level, I could feel one night she had other people working with her (she's charming and a good liar-I am not ha ha ha) sending me crap-I spied on them in the Astral. The sad part about it is the harder she swung at me the more it hit her back and she was/is so consumed by looking at me she has not looked inwards, where her problems truly come from and where the answer to stop it all lies! Keeping our slates clean is the best thing we can do, walk our talk and live with Truth.
So the war is nearly over...since this started she has (nasty lady or not, I still find it sad) managed to give herself financial problems, may be losing her home, husband is going to jail (they got raided), tenant moved out, her kid got injured in sports and another one was beat up by her boyfriend. I do wish she'd get a clue and see what is happening-I have tried to explain it to her and can't understand why she can't see the Truth and get out of this awful spiral.
I'm quite sure something bad latched onto her during a house cleansing but since I am the person who could help her this nasty thing has turned her against me instead-another reason I chose to keep it to self defense and not be nasty.... ...anyways that's how to deal with someone who wishes you ill while keeping your Karma clean.
Another one I have used on people who are fake and tell lies that cause you grief is also very simple and works very well. Light a candle, burn some sage or whatever you like as incense, breathe and meditate...and ask for that person to be seen for who they really are. again you have thrown no ill at anyone, but the results are not pleasant for the jerk in question ;-) The last one I threw this at was demoted at work, they saw him for the incompetent fool he is.