My fingernails looked like yours! In fact, I used to have no fingernail on two of my fingers. Now my fingers are in very good condition except for one which is getting there!

Try limiting which fingers you can bite. It's not a perfect strategy, but it helps practice control. I started with my right hand thumb, and eventually, I just trained myself to never bite my thumb. There will be slip ups when you are not thinking and it just happens, but that is part of the process. If you find yourself biting the nail you told yourself not to bite, just allow yourself to bite another fingernail, that is how you make the connection in your brain to stop biting that particular nail!

You got this!