If you really want to improve any area of your life, you have to courageously face the things you can do right now. Do those things and experience the next level of life. Repeat this process to the level of success or happiness you desire.
Are you one of those people who is aware that you bite your nails but have not found a method to stop biting nails that actually works in the long term? I can completely understand how you feel. You constantly put your fingers to your mouth and it is only after you have started biting that you catch yourself doing it.