The author of Psycho-Cybernetics, Maxwell Maltz, wrote a book about exactly this issue: how to prove to oneself that bad events are not the only possibility, in order to shift the subconscious’ kind of needle on the “what’s normal” gauge.
I highly recommend the book but the tl;dr is that you invest some time in imagining different kinds of experiences, with as much focus and emotion as possible. Treat it as a proper project and not just daydreaming.
Like if every time I met a cat as a child, it scratched me, and I know I’m now so weird around cats that they act that way regardless, I would imagine going to a friend’s house or somewhere safe and seeing a cat which is friendly, and I imagine feeling it curled on my lap and so on, to prove to my mind (which he contends, and I agree, can be programmed by created images as well as actual experiences) that cats are cool… you get the picture I’m sure.
He’s kind of saying, if reality has not so far delivered you the programming you want, you must intentionally create your own, then your subconscious, which he defines, correctly I think, as a servo-mechanism and NOT a dark force trying to sabotage you, will believe that’s what normal is, and act in all ways to establish it.
Because the servo-mech is programmed to think all cats are dangerous right now, it delivers that, and once its programming has been changed it will deliver different things. Psycho-Cybernetics is the foundational work from which the whole, rather overdone and played-out, self-help industry originated by the way.
His original concepts are simple and logical, and each successive generation of authors put their own spin on top, maybe from what worked for them but probably also just to market themselves as unique, until the original messaging got lost.
If you check the book out, get the old version with the red & white cover, not the newer one which is some kind of commentary and according to Amazon reviews, not as substantial. It’s an easy book to read.
I did a post about it a while ago here: Getting your subconscious on your side
Yes, kind of useless without a “how.” 