My roomate is a thrird degree wiccan and warded our new house because I felt horrible negativity. I was moody and feared what was the presense was. I know what you are going through.
I would cast a circle and light some white candles and some sage and use your athema to focus your energy to counter act the negative then walk around the house with your athema and salt. Go into every wall of the house and draw a pentagram in the air and say. " I banish negativity from this space, no negative energy shall enter," and while you chant, spray salt in the corners. While you are concentrating on banishing, visualize yourself surrounded around you, protecting you and push that light out further expanding positive energy.
Then take o your white candles and leave them by each window in the moons light to burn itself out.
I would also suggest you do this spell durning a full moon for extra moon magick.
Your house should be safe after that, It worked for me and this was an original spell I came up with for this peticular occation.
Blessed be and be safe, May the Goddess protect you and your loved ones from harm.