Membership in an LLC in the State of New York is a dangerous risk without an operating agreement. You seem to indicate that you do not yet have an operating agreement. Without an operating agreement, there is a very limited set of circumstances in which a member can withdraw from the LLC. You should speak to a local attorney to discuss the specifics of your situation to determine whether you are a member at this point and, if so, whether you meet the requirements for being able to withdraw.
This answer is provided for information purposes only. Only an attorney familiar with your specific situation can provide you with legal advice.
This answer is for discussion purposes only and you should contact an attorney in your area. No attorney client relationship is being be created here.
The short answer is that you are probably not a "member" yet, per se. It's my understanding that NY requires LLCs to have a written operating agreement. That being said, you could still be on the hook for breach of an oral agreement/partnership if you're pulling out. There's a lot more facts that could affect this. Best of luck.
When you filed the Articles of Organization, the entity was created. However, only upon executing an LLC Operating Agreement do you admit members. Getting rid of a member is governed by the Operating Agreement. You should consult counsel to help you draft an Operating Agreement.