Dependent personality disorder is a mental condition in which people depend too much on others to meet their emotional and physical needs.
Nicotine is the chemical in tobacco that keeps you smoking. Nicotine is very addictive when delivered by inhaling tobacco smoke into the lungs, which quickly releases nicotine into the blood allowing it to get into the brain within seconds of taking a puff. In the brain nicotine increases the release of brain chemicals called neurotransmitters, which help regulate mood and behavior.
Dopamine, one of these neurotransmitters, is released in the “reward center” of the brain and causes improved mood and feelings of pleasure. Experiencing these effects from nicotine is what makes tobacco so addictive.