Some people do see orbs in real life. But they probably keep quiet about it mostly unless they know the listener is open-minded. Spiritual, emotional and mental dirt build up in a place or around an object in just the same way as physical dirt does, but a lot of people think you're utterly wacky if you dare to suggest we're anything more than bags of water, bone and meat...
Shadow forms are real; I'm very, very sceptical about woo these days, having met a lot of charlatans over the years (along with a few genuine folk). I've seen them in the shape of people near a house round the corner where someone died in mysterious circumstances (I didn't know this at the time, I just couldn't work out why there was a dark man-shaped figure near my car that then disappeared) and I've seen them as black misty wraith like things in front of the car when driving.
And then, to lighten the mood a little, there was the ghastly little ghost of my friend's dog that came and humped my leg one night when I was staying with them (he was a ghastly creature in life as well, very spoiled, highly strung and untrained). I wasn't the only one who saw it, either; someone with us saw it too.
If you're looking for something to help, OP, boil some water, dissolve some rock salt or sea salt in it, let it cool, say the Lord's Prayer over the water, stick the mix in a spray bottle, and spray the rooms where you're uneasy. Say the Lord's Prayer or other long-standing religious words from your own faith with a couple of centuries of power behind them. There are other cleansing things you can do as well: smudge rooms, items, and yourselves with a little incense, for instance (sustainable, obviously...) And if you're really worried, have a word with the local holy man or woman, they'll be able to advise on exorcism/cleansing.