You're not worthless. You're more than your stutter. You may feel like your stutter colors the way others see and hear you. But you exaggerate that in your mind to more than it is. Feeling worthless impedes your ability to form bonds and relationships to a much greater extent than your stutter does. How can you function in this life? You work at it. You pick a direction and you get moving. It may not be easy. But your accomplishments will be all the greater for the difficulties that you overcome. Did you have any luck finding a speech therapist?