Hello fijiisland: I also have things in my past I did... some awful things... some just twisted & bizarre. I have often thought that I hope I could be said to have been mentally ill my whole life. Because, if not, then that means I was simply a bad seed. Some of these things I can never talk about. Others I have talked about slightly with one therapist... but not in any depth. I also carry allot of related guilt & anger... much of it focused on myself wondering how I could have done what I did...
I have an on-line acquaintance who lives in the U.K. He is a devout Christian. I'm not a religious person, myself. But, if I were, I'd want to be like him. He & I have corresponded, in the past, regarding the concept of "forgiveness". He maintains that self-forgiveness is always possible. I, for my part, maintain that there are some acts so egregious that self-forgiveness is simply not appropriate or possible. (I put myself in this category.) What I try to employ, as a substitute, is simple acceptance. I strive to simply accept, as thoroughly as possible, the fact that I did what I did & then move on in whatever way I am able. It's not a great solution. But, over time, I have found that the burden does lighten... if just a little bit...
I send warm thoughts your way with the hope that you will be able to find the inner strength to lessen your guilt... and anger...