I could make a suggestion that helps cleanse the house of negative energies...If it's anything more diabolical than that - I would seek help from a professional. I've seen situations first hand where it requires someone who very skilled at what they do. Anyhow, sweet grass + sage + cedar. The combination is better than using sage alone. Basically, you are demanding the "energies" to leave. Smudge every part of your home. You can even use salt water and splash it throughout your environment. Remember when removing energies like these from a space it tends to leave a void, so you must replace it with some positive energy. I usually burn some herbs to amplify home and hearth (I've used rose petals, carnations and Rosemary). More importantly you have to be firm and strong willed in your intent. Purge your environment by removing anything that has a negative attachment to it. That is about all I could suggest. My strongest advice would be to seek help from a professional (one that corresponds to your spiritual beliefs), but these cleansing tips have helped greatly for me, and others, when they were applied in a serious manner. Please note, I do not specialize in this, I'm just sharing a practice that I've had wonderful success with. If there stronger forces at hand - heed the help of a professional, some things shouldn't be attempted alone. Good luck.