I once worked with a lady whose husband was a recovering Meth addict. She theorized that certain people had "addiction personalities." Her explanation was that some people are prone to addiction because of either genetics, or something that has happened to them. I don't know enough about addiction in general to agree or disagree with her statement, but I found it interesting nonetheless.
My uBPDM, I am fairly certain, is addicted to prescription medications including barbiturates. She occasionally goes cold turkey off her meds and acts all proud of herself as though to say "see, look! I can quit whenever I want to!" But if this were her choice, she would theoretically not need a refill on that medication until later than usual correct? That's never how it plays out though. She gets her refill exactly when the pharmacy allows, regardless of whether she went cold turkey a couple of days or weeks.
I am also fairly certain she would be an alcoholic if not for those same medicines. They don't play well together... But despite the fact that she has always said drinking is bad (moral standpoint with her) she will drink anything within reach if she's feeling down enough, and generally too much of it.
Her medications and health problems are all she talks about. She has no hobbies, no interests, no anything else to occupy her thoughts. Phone conversations are solely about her health and doctor/ER visits. I'm sick of listening, everyone else in the family is also sick of listening. What she doesn't realize is that she is very close to alienating everyone in her family circle (she already has no friends) because of what she allows to rule her every waking moment.
She absolutely thinks she is in control of her medications. She absolutely thinks she isn't addicted to them or the endless cycle of doctor's visits and mini health crises. She has no clue that anything is wrong, never goes anywhere unless forced by need, and doesn't understand why with each passing year she gets fewer and fewer Christmas cards in the mail... It's sad. But there's nothing I can do about it except protect myself from the cycle of self-destruction. I do that with distance, primarily, and VLC.
It may never make sense to those of us that don't have and have never had an addiction. But that may actually be a good thing, and keep us out of the same dark hole.