Anything we do again and again in response to a stressor or any given situation, if it helps?
It is habit forming. Addiction and dependence aside, it helps us cope.
I may have a habit of chewing my nails or picking my nose(no I don't).
One is triggered by stress likely, the other by not having the proper tool for the job.
In the end though they are automatic responses that have a soothing effect for us.
Not addictions not dependencies just automatic responses or habits.
I'm no rocket scientist obviously, but anything we do repeatedly over time is a habit.
My fingers will bleed or my head may have to cave in before I stop.
If I continue to do harm to myself it is still just a habit, simple as that, nothing else.
IMHO. Cheers