How to break a spiritual contract made discarnately? (if possible)

[AnthroHeart]

Can you meditate? That would be a first step I imagine.
If you wish, you can ask Archangel Michael to provide protection with white light from those psychic attacks.
Prayer can also be of aid.

I've been where I was freaking out because of my mental illness and thought I had to kill myself. Meditation helped me the most.
My mom works with archangel Michael when she's healing people.

What's really good though, and I do recommend, is to get some white sage, and burn it in your home.
Let the smoke fill all areas of your home and say "This space belongs to me and my family. Only the light may come here. I banish all negativity from this space."
Be sure to leave a back or front door open while saging your place.
Sage clears out negative energy and leaves a neutral feeling behind. That may provide the relief you need.

I'ma do this too! One question though: Can they use the doggy door?

I think it makes things easier if the door is open. It allows the smoke to go out too. It's not bad, I like sage smoke, but it does get thick.
It doesn't set off my smoke alarms though, which is interesting.

Can the door just be cracked? Maybe I'll leave the door to the garage cracked and the garage door open just enough that I could see a person being able to crawl under it. Not my fault if leaving my house is a huge pain in the ass for malevolent entities. They shouldn't have been here to begin with. Not that I harbour ill will against them. Just sayin'...

Anyway, I live in Florida, man. We got mosquitos out here like a motherfucker.  Are you sure these malevolent spirits just can't use a doggy door? I'll gladly take the smoke over the mosquitos. Plus, I can crack a window (with a screen in it) in my room, like I used to when I was a pothead.

So seriously, are you SURE they can't use the doggy door?

I think your intent is the most important. I've saged with my doors closed before, and that worked. I don't see why not.
I was just recommended to open the door. But if you can't or prefer not to then that's fine.