How bad habits are formed and difficult to stop

 1- STRESS BOREDOM AND LONELINESS: Some habits are form due to the person mental state. If you are stressed up your body release cortisol into your blood stream, it weigh you down, you feel like resting,if you are missing someone or something you are lonely, if you are doing something you don't like or you are just there,without any interesting activities,then you are bored. In such situations your brain crave for something more interesting by so doing you develop a bad habit of any kind such as MASTURBATION just to help the situation and enjoy the temporary moments other habits are form too like pornography, smoking, drug intake even habits that leads to continuous crime. 

Hence, anytime you are in that state of stress, boredom or loneliness you repeat the same bad habit again, occurring over and over again it makes you develop less resistance to break such habit, because you are in a similar situation that fertilised and birth the habit, before you know it, it becomes your second nature difficult to break but easy to make.

2- THE BASAL GANGILIA: 
The basal gangilia is part of the brain in the prefrontal cortex it is responsible for our emotions, memories and pattern recognition. When you are engaging in new habits, the brain learn the new habits, if the process repeat itself again, you kick start the basal ganglia. 
Immediately the behaviour becomes automatic the decision part of the brain stops responding, you have switched between stop to go creating a loophole for you to repeat the habits as often as possible the damage is already done, the bad habit is in control, you are now a puppet in the hand of the bad habit influenced by the basal ganglia,at this stage the habits difficult to control or break.

3- DOPAMINE: 
Dopamine is a pleasure addicting chemical in the brain it is released when you engaged in enjoyable behaviour to an extent that you are high in practicing the new habit,if you continue to repeat the habits and indulge in it, your brain is altered which force you to seek for it again. Your brain becomes dependent. It is trapped. You are now addicted it is a difficult task to stop the habits.

4- UNSTABLE MIND (COMPULSIVE NATURE, OCD and BIPOLAR DISORDER etc)

A person suffering from Obsessive Compulsive Disorder, Bipolar Disorder will find it difficult to break bad habits and likely to practice or fall into more easily than those who are not having such disorders. Obsessive compulsive disorder possess the compulsive nature to continuously practice bad habits due to the wiring of their brain that produces more addicting chemicals that attract corresponding behavioural habits as it where. It is a compulsive urge to fall easily into bad habits which is hard to break in the long run. Those who have a compulsive nature have a similar effect on their behavioural pattern like Obsessive compulsive disorder in less version of the intending bad habits but more like to break than  OCD sufferers.
However, Bipolar on the other hand can easily subject to bad habits in accordance to their mood swing(manic episodes), a state of low energy (sadness) and high energy (over happiness). In their low energy state they are likely to repeat and indulge in bad habits, while in their high energy state they are likely to fall into new habits and maintain the old ones due to their risk behavioural addicting nature, creating less window of freedom to break their bad habits,even if they have the resolution to stop the addicting bad habits, they fall more into it and the cycle repeat itself.

5- INTEREST AND PERCEPTION:
Our interest and perception on morality often determine how will indulge in certain habitual behaviour.An individual whose moral compass is below average may form bad habits easily,caring less for the spiritual, societal and moral implication or views. They tends to practice such habits to extreme in accordance to their desire interest and perception subjecting the mind to it subconsciously that reminds them that the habits have been avoided for a while,a kind time loop reminder in the mind. They have less desire to stop such bad habits anytime soon. However,there are individuals with average, and above average moral compass with higher interest on their desire habits as related to genetic design or heredity. They have normal perception of such bad habits to be wrong, but they can't help it not to engage in it, in fact most in this category often find it more difficult to break the new developed bad habits and are prone to fall into it easily and repeatedly, they find it hard to stop if the act is repeated in span of time at close intervals. The more closer of the existing practice habits(span of hours, days, weeks or months), the more they are likely to indulge in it, the stronger the habits over their self-control and self- discipline.Also they are likely to be tormented by the bad practices on their conscience through guilt and religious view point and belief. 
In some cases they are people who are intermediate in between the two moral compass their situation is often unpredictable. Some easily form their bad habits and not too difficult to break such habits, others form it easily and hard to stop the habits.Their situations is due to their individual differences and circumstances.Hence,bad habits is easy to make but hard to break.