It's impossible unless...
It’s not useful to think about assumptions or beliefs as right or wrong. Its more useful to think of them as helpful or harmful. Get rid of the harmful ones and keep the helpful ones.
A simple way to challenge any assumption or belief, is to ask yourself (in your most sarcastic tone of voice) Reeeally?
Good people make and often repeat bad decisions for very good reasons - its our exaggerated fears that cause us to resist making good changes and exaggerated frustrations or expectations that cause us to over-react and make bad changes.
Our 2 biggest Achilles’ heels to a better life are our two main coping mechanism - lowering our expectations or finding someone to blame.
Two important questions to ask yourself before doing anything - Will this really help me achieve more of the goals important to me, and even it it does, what am I giving up by doing this?
We are all special, but we are not unique.
What you cannot quantify, you cannot justify.