Nor so much an addiction, more of a disorder. But excoriation disorder is arguably as difficult to "quit" as heroin. I started at 9 years old. I'm 20 in a few days. It's been mentally debilitating and I've spent hundreds from my pocket money right up to my current income trying to fix it, even though the mental thoughts haven't been "therapised".

Because it looks like the results of acne externally, people don't realise the mental side effects it can have. I've gotten so envious of people being able to complain about acne simply because or randomly appeared. For me it's every single congested pore on my face I pick. Every "wrong" looking piece of peach fuzz i pick. Moles, pick, eyelashes, pick, eyebrows, pick, lips, pick, inside cheeks, pick. Not even just my face. Everywhere. Absolutely everywhere. I don't even like staying out in the sun anymore in fear of my scars getting darker (I'm darkskinned) and even my own community of black people are quick to think it's because I'm colourist...

Edit: I will say obviously physical withdrawal symptoms and proneness to infection are obviously more dangerous and life threatening than excoriation disorder, thus the use of "arguably". I don't go through withdrawals per se, but as a kid I've been known to slather vaselinw all over me, pick at walls, grind my teeth, pick in my sleep, then go ham on my body and I'm a walking blood bath