Full disclosure:
I am just some rando on the internet and only share
what I hope will help. In no way is the below a
replacement for professional counseling.
> The problem is I know that I am completely addicted, but I cannot stop. I feel like I'm the alcoholic drinking a bottle of vodka a day. I have tried to give up many times but I just can't crack it.
My first recommendation is to try to not beat yourself up about this. No one knows how to hurt you more than yourself.
My second recommendation is to take small steps and allow yourself time for each new habit to become entrenched. For example, keep your phone in your pocket instead of visibly near. Once that feels natural, incorporate the next habit which you feel reduces the device's prominence in daily life.
> I have tried all kinds of blocking software and strategies. Blocking software, however elaborate, never seems to make a different.
As others have mentioned and you describe, using an app on the device to alter dependency on the device likely will not work as the device remains the focal point.
> This is a really tough nut to crack. I think there is probably no technological solution to it.
It is and I believe you are entirely correct in identifying "no technological solution to it." If we pursue this hypothesis to its logical conclusion, then one or more solutions must exist outside the technical space. Which suggests a solution might be found in the behavioral space as the two actors in this scenario are a person and a device.
I'm not saying this will be easy nor simple, only that I hope you find peace in finding your solution.