Addictions can be seen as complex and very difficult to overcome, especially for the sufferer.
However, some recent work on addictions has focused on how they can be interpreted as a manifestation of a lack of love, a lack of belonging, or a lack of care that has left an emotional hole in someone. When this happens, that hole tends to be filled with whatever is easily available- drugs, alcohol, sex, gambling and so on.
Of course some addictions come with physical and medical issues, and these really must be dealt with by specialists. But other addictions can be helped enormously with therapy.
IMPORTANT: Addictions are NOT a sign of weakness, or stupidity. They are NOT a punishment. In many cases they are just a habit that you have learned to cope with an emotional gap in yourself. There was a time in the past when it perfectly fit the hole in your life. So of course, you try it again. Over time it becomes a habit and usually over time it becomes less effective so you do it more, which enforces the habitual behaviour, and so on.
So just because you have been diagnosed as an addict, or believe yourself to be an addict, this is not a life sentence. For some types of addiction such as alcohol, it is best and most successful to have a controlled and supported withdrawl from alcohol, so it does take time, but progress can be made.
TOP TIP: for smoking a classic way to help break an addiction is to collect all your cigarette butts and ash over a couple of weeks, put them in a large jar of water with a lid, shake the jar, open the lid and take a big sniff! It will of course smell disgusting. By doing this, you replace the ‘good’ feelings you have from cigarettes with the memory of the horrible, nasty smell, and this then makes smoking repulsive. Keep the jar and keep sniffing.