I'm a fan of supporting the positive...
When the corner we lived on became "the spot" for illegal transactions (of all sorts) I started mixing up buckets of miracle-gro, charging them with positive "growth" images, and watering the curbside plants. I wanted to "grow" miracles, and "grow" health, and "grow" opportunities that would lead people away from the behaviors they were engaging in on my doorstep! I also hung up windchimes and visualized the sound of the chimes cleansing and protecting everything within earshot of their music. I also used chalk to draw designs over windows/doors that could capture/redirect/bounce back negative energy and hung prisms in the windows and on my porch to "transform" the negative energies into positive. Oh, and I mixed up buckets of water, salt, and an essential oil (peppermint, lemon, rosemary... something cleansing and uplifting) and used that water to clean... I'd dampen a dust cloth and wipe down the walls, wash the windows, mop the floors, splash off the porch (just keep the salt water off the plants!).
Anyway... I'd suggest that she try something similar. Certainly get her involved in cleansing the space physically as well as psychic/emotionally. Open the windows and doors, wash things down with salt water, smudge the rooms, ring the bells, and chase the old/negative/stale energy out. Hang up prisms and windchimes and suncatchers to continue the work of transformation. Close the windows and doors and bless them in whatever way feels right (and don't forget that phones, computers, water taps, and chimneys are also "entrances" to the home... make sure they've been cleansed and blessed too!). There are lots of options that would mesh with any decore... from hexmeister signs, to herbal/floral swags, to symbols drawn with salt water, to suncatchers, to window decals, etc. Bake cookies or a favorite meal so the home is filled with comfort. Maybe add some herbal pillows to symbolically "soften" any falls?
I admit I'm not much for ceremony for the sake of ceremony... I try to combine the practical with the spiritual. So I always mop/clean with charged water to get both thet physical and the energetic "dirt". She may want to think about ways she could build protection/cleansing but also the invocation of the positive into her daily routine. Perhaps making and then wearing a piece of jewelry that will act as a reminder to ground/center/focus? I'm a huge fan of bracelets/necklaces that act as "reminders" as well as jewelry... and she can find basic beads at almost any craft store... maybe onxy or obsidian or hematite to drain negativity and protect, a few rose quartz and amythest for self love, and some carved bone beads for strength? I find many of the beads I use at Michaels/AC Moore, just be careful not to grab the "simulated stone" versions!