Addiction

Our body always finds a coping mechanisms to deal with unmet needs, one of which is seeking the feelings of ease, comfort, safety and care through products or patterns of behaviour which we then label as all sorts of addictions. Therefore to overcome addictions it's important to understand what is causing the need to self sooth through them.
There are loads of reasons but they all come back to a broken relationship with self and or some sort of external trauma / situation causing the inability to meet the body's needs.
Therefore it's important to focus on understanding yourself rather than punishing yourself. At the end of the day, it's the only thing the body realy needs. Because the lack of understanding and care is what caused the addiction in the first place.
A lot of the people who rely only on self discipline to get over an addiction often just end up becoming addicted to another coping mechanism.
For example, they stop drinking but then they become addicted to extreme running / excersing that can end up being self destructive as well. Or they stop smoking and start overeating.