Hi and welcome to the forum. If you dont want to go to NA then i would suggest an addiction counselor/therapist. Hopefully at some point you will be able to talk to your family about this. Our secrets keep us sick. Please reach out and get the help you need. It is no life being chained to drugs. You deserve to be living a happy life.
Cocaine is a horrible drug; it just wrecks your body, so I'm really glad you want to stop.
From what you've wrote it seems you're admitted you can't stop on your own. The answer to your question is: You ask for help. You have a bunch of options, luckily: you can talk to your family doctor (who has to keep this confidential; he/she is bound by HIPPA laws) or a therapist. You also can check out any AA meeting or NA meeting. NO questions about your identity will be asked.
Cut off all contact with your dealer. Delete saved phone numbers, and don't hang out with people who do drugs.
Nip this in the bud now; you'll be so glad you did. Getting sober is not that hard; STAYING sober is a challenge, but it can be done. I encourage you to read thru this forum and to see what others have done to successfully recover from this beast of disease: addiction. Come back and talk to us some more.