OP, is there something at the back of your thinking that says if I am a really good Catholic now it will balance out my past?
Or that if you stick to the rules perfectly then you won’t make the mistakes you made in the past? Or feel the way you once did?
Because what I don’t hear in your post is that you have cleared the slate completely. Have you forgiven yourself, unreservedly?
Because, as someone upthread pointed out RC does seem to have as its stating point this idea that we are born flawed. If you take another position, that is not contrary but perhaps more in the spirit of real Christianity (Jesus, forgiveness, kindness) of we are born fine, just the way we were meant to be, perfect in our natural imperfection, then it takes the pressure of you to correct an abstract, philosophical view of the self (that in my opinion leads to dogmatic thinking). These rules are guides but at the point they cause you anguish they are no longer relevant.
A very wise priest once pointed this all out to me.
You are perfect, OP. And flawed like everyone else. You took some turns that weren’t right for you but you have to let all of it go. It’s all about the future and best intent amongst the real world demands on you. The RC church has actually woken up to that now a bit, but as others have said, if this is what you want, then it is between your conscience and God with Jesus as an intercessionary figure - not the priest who is just a bloke.
Choose peace. Mental peace. I believe that any God who creates would want that for their creations.
Apologies if I have read too much into this or projected. I think a lot of people can pick up on a sense of genuine distress in your post.
To the others who still have a view of confession based on Godfather films, I’ll informed internet sites and their own bigotry ( rapists and murderers can just confess anything and get off) I would ask you to engage your brain and really think that one through.
Lastly, sin as a concept is about doing something that does not protect, maintain or add to your emotional, mental or spiritual well being. Mortal and venial sins were classified as such to understand the effect of behaviour on the human psyche. Old terms, but they come from Latin.
Perhaps, in light of the damage we inflict upon ourselves in modern society, such awareness is not redundant?