Touching my earrings. Literally all day, at least 1,000 times a day I grab my earring and push the back in & out. I've been trying to break this for years and it never works. I will take earrings out for months at a time to train myself that there's nothing there, and I still keep grabbing for it. Then I eventually put earrings back in thinking it's safe and I go to town on them again! Ugh it's so annoying!
When my husband quit smoking, he explained to me "Imagine never being able to touch your earrings ever again- even though they are right there within reach- that's what it feels like for me to not smoke". So freakin proud of him for doing it!