So how did I finally quit biting my fingernails? Only one thing ever worked for me: Love. Love your nails. Love yourself. What gave me the psychological strength to quit was a friend's observation that nail biting was his least favorite of "all the self-destructive habits". I had never thought of nail biting as self-destructive or self-hating. For me, the act of nail biting was just another obsessive-compulsive quest for perfection. Silly as this seems, at the level of my habit I believed that if I kept on biting them down I would finally achieve ultimate smoothness and perfection. This same friend also bestowed upon me another painfully obvious gem of wisdom I had somehow overlooked: "They are nails. Just leave them alone and they will grow. Trust me." He and I are not friends anymore but his words made an immediate and lasting impact.
That was the inward part of love, finding the truth about the relationship between you and your nails. The second part of love is giving tender care to your fingernails themselves. The easiest way to change a habit is to replace it with something else, preferably something healthy. Some people use gum or toothpicks but I prefer to actually go with the flow and focus the attention directly on my nails. Try to think of positive and healthy ways to interact with your nails. My main replacement habit is filing. I recommend getting several different kinds of files, from spongy buffing pads to coarse metal files and emery boards. Shape, grind, smooth or fashion those nubs on the ends of your fingers any way you want. File slow and gentle or hard and fast depending on stress level. It also helps to have nail clippers and small cuticle trimmers handy for cutting emergencies. Never bite - always cut or file.
Stop obsessing about the negative appearance of your nails. Pamper them. Imagine them long and beautiful. Imagine being able to open a soda can with your nails of steel. Feel the joy, the pride. Feel good. Keep your file and clippers nearby at all times and file your nails as often as you need to keep them from bothering you. Soaking fingernails in vinegar twice a day for 5 minutes will make them less brittle. Take supplements like Vitamin E oil and/or brush or massage it directly into the nails and cuticles. Find a hand lotion you really like the smell of and use it liberally throughout the day. Spoil your nails with love and attention and they will blossom under your patient care.
A note on backsliding:
It would not be an exaggeration to say that I have been biting my nails since I grew teeth. Little kids learn by imitating the people around them and both of my parents and my only sibling were all nail biters. I was doomed from infancy. A naturally competitive perfectionist, I took nail biting to the next level. Some people bite casually, a little nibble or gnaw here and there when stressed. Not me; I always had my hand twisted up around my mouth, ripping and biting them bloody. I could even rip the little ones out by the roots, I was so good.
Scroll forward 30 years. As of this writing, I have one un-bitten nail and nine bitten ones. I do not feel bad about this because I know the nine will grow again. More specifically: I know that I will let them grow. I know this because I had just quit biting my nails for an entire year. Then, six months ago, I quit smoking cigarettes. This had two unfortunate side effects: I gained over 25 pounds and, not surprisingly, I started biting my nails again. It was a tough trade but I have no regrets. I have now lost most of the weight and have intermittent control over my nail biting habit. The most important thing is that I have the faith and confidence that comes from beating it once. I can do it again, once I commit to giving positive attention to my fingernails and make it part of my every day habit until it becomes my identity again.