I'm 19 years old and can not break a thumb sucking habit it's never public but is becoming a problem what are ways to stop thumb sucking?

Clinical hypnosis: Hypnotherapy when performed by competent clinical hypnotherapists can be effective. Most clinical hypnotherapists are psychiatrists so consult your local psychiatric society to find help in your area.

Treat Impulse D/O: Thumb sucking is a type of an anxiety disorder called an impulse disorder, like impulsive shopping, nail biting, etc. There are specific cognitive behavioral techniques for treating impulse disorders (may apply ocd response/prevention techniques) and medications (high dose ssris and atypical neuroleptics). www.ocfoundation.org for support. Ask for help.