Hello jacrob,
Seems like those visitations are/were causing you some trouble. I'd like to relate some of experience dealing with negativity, and perhaps there might be a thing or two in there that will inspire you. I'll try to make it as short as possible.
About over two years ago I learned a close relative (my mother) had dealings with very negative entities, sometimes consciously and sometimes not. She has always been a very negative person dwelling in victim-hood and thriving in states of sickness, looking for others' pity and attention. She is also a very good manipulator, especially when it comes to emotions. Although I knew her house was haunted to a certain extent (I lived there until I was 17, moved out because I wanted freedom and to live with my lover - looking back now I see my willingness to move out and put 250km of distance between us might have also been fuelled by a subconscious need to get away from the negativity asap) I only learned she was dealing with higher density negative entities later in life. The medium which I trust and who stumbled upon my mother's situation calls them "demon" and although she's helped so many people clearing their houses of negative entities and ghosts, she felt powerless in front of what my mother was surrounding herself with.
Long story short, we discovered this because on my side I was receiving visitations more frequently in my home without knowing why or where they came from. It was becoming very unsettling and initially I was quite scared. When I discovered the source, I tried to speak to my mother but she wouldn't hear it, sometimes admitting of dealings with "demons", sometimes completely denying everything and ignoring everything I said. At the time I was struggling and did not know what to do, so I decided to completely cut her off my life, alongside everything that came from her. That did it at the time; visitations decreased dramatically and life started getting better again. The year and a half I spent not talking to her was extremely peaceful. Since then I've learned lots about my own growth, the universe, peace and dealing with negative entities, but looking back I realize at the time I was not ready to deal with all this. I did not know how to handle it.
From your opening post I see you know the importance of unconditional love when it comes to all beings, including negative entities. I've learned it too in the last few months; you don't fight fire and fire, it's pointless. It's no use getting mad or worse, scared. Some experiences can be quite unsettling but I've learned to bring calm within myself when I am facing something negative and send it love and light. I imagine the being surrounded by light, the creator's love, and transformed into something very beautiful. In terms of the vibration of our home, I've also come a long way since 2-3 years ago; it is now very peaceful here. I have a candle burning all the time whose flame I transfer to another candle when it's almost done. On an improvised altar, I also have an amethyst, like you
I don't really "use" it, but rather leave it there to shine positivity around our space. Every night before going to bed, I welcome all STO and light/love entities to come in our home if they wish to, and ask the light to keep the negative entities at bay, however sending them beautiful light and love healing. Rarely, it happens that something dark passes in our home but it never stays; it must be a bit uncomfortable for them.
Regarding the dark entities sapping your energy, I used to have something like that. My energy was being sapped by whatever connected my mother's minions to me at the time, and also by negative thoughts and emotions. I used to have thoughts which weren't mine, violent thoughts, and when I released them, boy, it felt wonderful! I expected the process to take long and to be tedious as back then I had never done any spiritual healing, but it was completely the opposite. I followed my instincts, sat on my bed, closed my eyes and brought myself into a state of calm. I then proceeded to visualize the dark energy which was affecting me. Not unlike your own dream jacrob, I saw in my mind's eye a gooey black tar attached to my back. I proceeded to send it light and love, disconnecting the threads, until in my mind I could see none anymore. I bowed and thanked the light for their help. The whole process took 10-15 minutes. And like I said, at the time I thought "hmmm well I'll have to do it again I guess, can't be that easy, right?". Well, it CAN be! The following day I checked to see if I could find the negative thoughts and emotions and they were gone! Completely. I had the memory of having them but I could not make them arise within me anymore. The link had been broken and healed.
Since then I use a similar technique to treat pains or release negative thoughts. It works very well, with one exception; if I don't take time to concentrate and do it properly, results will be so-so. But then it's to be expected of anything. Do it properly or you'll get more or less satisfactory results. Take the time
It's worth it.
Hope this will inspire you a bit.