Anyone with experience with the occult and rituals please read

I need some help, you guys. I know very little of the occult, and honestly have always been a little wary of it. I'm also what you'd call a "Gnostic Christian" and have been since I was a child. The past four years though, have opened my eyes to many terrifying and many beautiful things.

About 6 years ago I was visiting one of my closest friends. For years he'd been dealing with something. None of us close to him knew what was going on for real. Most everyone ended up deciding he was crazy, and most friends stayed away. But I didn't. This guy is one of my best friends; I've considered him a brother for 15 years. I didn't completely believe what was happening to him either, but I absolutely believed HE KNEW something was really going on. I just didn't know what it was.

One day about 6 years ago, I came by to see him. He asked me if I "wanted to see what he sees". I agreed; my only intention was to help my friend. He'd always said that "at least you believe me, man. That's enough". He told me to sit down in front of him and place my hand on a bible (KJV I'm pretty sure). He said to repeat something after him (to this day I cannot remember what it was) and to hold my mouth open. He said I'd feel a "sword" pierce my tongue.

I honestly didn't think anything would happen, but I did feel the "piercing" sensation. And that was it. About a year and a half later, I started hearing voices. Then the physical, mental, and emotional torture began. These entities knew my past, and my future at times. Those years almost destroyed me completely. Finally, one of the voices told me "bro, I'm not human". Something also guided me to a metaphysical website with a lot of information on the subject.

I'm a lot better these days; this experience has pretty much forced me to fix almost every issue I had in my life. Without this happening, I wouldn't be clean from an addiction that lasted for 14 years (been clean over a year now). These entities forced me to deal with the issues that kept me in turmoil (all fear-based emotional stuff; memories, past failures, etc). But I'm very aware that they have got just as much, if not a whole lot more, than I have out of the situation.

My question is, can any of you tell me what this ritual may have been or what kind of ritual it was? Are these entities demonic or familiar spirits? Is it a give-and-take contract of sorts that I entered into? And what can I do about this?

I appreciate any and all advice from you guys!