How can I break my lease in NY?

In mid-July while living in NY, I accepted a job out of state because I was struggling to survive and couldn't find a decent job. I notified the landlord through email. I moved out July 30. I paid rent for August and September and they still have my security deposit. I could not find a new tenant so I asked the leasing office I used to find the apartment earlier this year to help seek a tenant for me. The landlord's assistant said they, the landlord, would not look for a new tenant and I have to continue paying until the end of the lease or until I find someone to take over my lease. It's very expensive and I'm barely surviving paying for multiple residences. I've been very frustrated and stressed dealing with this office and the landlord refuses to respond to my emails or return my calls and his assistant only gives off attitude when I call. I don't know how long before a tenant is found, but I need an out.