Energy flows where attention goes.
This quote has helped me very much for the last several years. I also have felt like I have a negative energy attached to me. Although I do not blame it for any irrational actions. I blame myself. It is easy to place blame on something you can't see, but feel is there. (I also believe that this "entity" is just what I am calling my attachment to negativity)
If your attention is on negative thoughts, which it sounds like it is, then you are going to be more likely to be in a negative mindset inviting in more negativity. Outbursts like the one you had with cutting yourself is most likely YOU venting out the buildup of negative energy/thoughts/feelings ect. If you can shift your focus to something positive throughout your day, you can start on the path of happiness.
Letting go of things that upset you are extremely important, for everyone in our day to day lives. I used to get upset with my GF (at the time) for placing her gum on the rim of an empty glass. She would leave the gum on the glass, and the glass on the night stand for days. Eventually I would allow my attention on the mess build up my frustration. Then I would angrily communicate my feelings to her ultimately causing a fight.
Eventually I learned to LET IT GO. It really wasnt that important and it was much easier to just remove the gum, throw it away, and clean the glass myself. It may not have been what I wanted to happen, I rather she did it, but the outcome taught me this:
The glass and gum were bugging me.
The fact that she wasn't taking care of it bugged me.
I have the power to fix ONE of these problems instantly. Over time I did this with multiple things that would upset me and realized that I was allowing lots of little things to compound into something big. Setting me off and ruining my good mood. You can then measure the importance of happiness vs the trouble you have to go through to stay happy. If you are having to carry the weight of enough things from your partners laziness (or whatever it may be) and that outweighs the worth of being with them, then you are not going to be happy with them.
If you cannot forgive, you cannot forget. You can only choose one path.
I also believe its more likely that the reason you knew that something was up was not because demons were telling you, but because you have a connection with your woman and are able to read her. 3 times an ex I had a long time ago had sex with someone each time we broke up (3 short term breakups). I knew the very next day each time. I pushed her to tell me, and she would finally breakdown (the same way each time) start crying and then spill her guts.
Its likely your intuition, which I find is strong in me when it comes to people I care about and am around a lot. I also agree that you should seek some sort of help. Any kind of help is better than nothing. I don't think its impossible for someone to fix anything on their own, but some people need assistance. There is nothing wrong with that. If you think you can do it, go for it.
Right thought
Right action
Conquer your fears, conquer your anger. Strive to be happy. Don't give in to negative action.
"Energy flows where attention goes"
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