Security Deposit Refund?

I signed a cob-job lease when i moved into my apartment and paid $1000 to move in (first months rent and security ($500/$500.) The lease stated that i had to give a 30 day notice when leaving my tenancy. The lease expired and i requested a new one be drawn up several months ago to no avail. I now am moving and admit i did not give sufficient notice because i found a new place really quick and had to make a deposit and what not. My notice was only like 2 weeks or so. The first thing out of my landlady's mouth is that "i know i will not get my security back right?" she says to me. Can she legally keep my whole security deposit for my not giving proper notice when the lease is over. There is nothing about month to month or anything. My landlady has not ever given back security according to the neighbors. Any advice?