Some advice on potential curse/negative entity effect, pls.

So, this might seem like a strange request, but increasingly it's something I've been giving more and more credence to.

Many, many years ago as a teenager I had a friend whose mother was big into a local spiritualist type scene. She was a professional astrologer, IIRC. Once when I was visiting their house I briefly met friend of his mother who was also from that scene. The next day my friend told me that this second lady was renowned for her "second sight" and after meeting me had said to him that I "had a demon on [my] shoulder" which would cause me problems if not attended to. I was very much a sceptic back then and just laughed it off.

Fast forward to today, I'm in my fifties and despite having many advantages in my upbringing my life has certainly not gone positively over all. It's been a real case of one step forward, two steps back, and while I will always accept responsibility for my own mistakes, it really seems like outside circumstance keeps pulling the rug out from underneath me, for decades now. Last year was very difficult for me, and things aren't great right now and I keep thinking back to that idea of a demon (or something) attached to me and sabotaging me.

Probably sounds all very dramatic and self-justifying, I know. I know that, demons notwithstanding, even a belief in being "cursed" could subconsciously affect your behaviour in tiny subtle ways which can make it appear true, and likewise the opposite can be the case.

I'm open to the idea of some sort of entity leeching off me, but also that just the belief in the something like that could have a powerful negative effect on the course of my life.

So, whether there is an actual "demon" involved, or a more prosaic reason, what might realistically be done to deal with that? Since the explanation offered to me all those years ago was an occult one, I suspect engaging in some sort of ritualised banishment or similar would be the most apposite answer.