Tom finally quit smoking 6 months ago after having a heart attack. after a long recovery, he was invited out by a group of old high school buddies. during the course of the evening, tom smoked a few cigarettes. the next morning, he bought a pack of "low tar" cigarettes, thinking to himself, "i just can't break the habit." this illustrates

The answer is abstinence violation effect.

Explanation:

This effect, abbreviated as AVE, is presented when a person is engaged in a substance or habit, at least once, after having made a personal commitment of abstaining from it. It is very common that people under this effect engage continuosly on the activity again.

This first relapse is commonly attributed by the person as "a lack of willpower", or stating that "they are sick".

would it be plagiarism to copy and paste off of here? ?

could you go a bit more in depth with you question? it's quite hard to understand. as soon as you do that i will be glad to : )