FL child custody law, procedure to file supplemental petition to modify custody for the mother

A SUPPLENMENTAL PETITION TO MODIFY CUSTODY- I am the mother.: HERE'S MY STORY: At age 15 yr old I became pregnant- a marriage was arranged due to the pregnancy. However, shortly after my daughter was born I seperated w/ the father. In 1997 the marriage was dissolved and I was awarded PRIMARY RESIDENCY. In 2002 I had a rough patch in my life and turned to the father for help because I did not have ANY FAMILY. The father AGREED but 3 weeks later I was in court for TEMP CUSTODY to the father. At the time I was under severe DURESS and agreed. The court stated that visitation to be frequent and aggrred upon both parties. Afterwards, the father only allowed me visitation every other week and NEVER during the school week. He never would talk to me directly instead through our daughter. 3 years ago I went to the father and told him our daughter expresses that she wanted to move back with me and that she was not happy. He became violent and physivally abused me but I didnt report it. However, my daughter did witness it. For many years I have been intimitated by this man and he has always told me "I GAVE UP MY DAUGHTER". I really jus needed help but was made to feel guilty and ashamed. Recently, I have filled a petetion to modify custody because my daughters grades are suffering and she is unhappy living with her father. She is unable to be herself and in addition, he has remarried and 4 more children have been added to the household. My daughter does not recieve one on one attention and she lacks self esteem + she is overweight. She is 13 yr old 5'8 and 175 lbs. More importantly, she is CRAVING a MOTHER so badly. To top everything off- THE FATHER IS UNEMPLOYED and has been for several years. He lives off of the other childrens child support. Recently, he has been physically abusive to his 10 year old nephew. There is an open case with DCF but I here that he could just get anger management classes or parenting. Despite all of these findings I have been told that its a 50/50 chance of regaining custody back of my daughter because I waited so long.. Please help me to find DIRECTION to the best way possible in winning my case. Anything like evidence or something I should be doing in the meantime. Oh, I have a great career and a stable enviroment fo my daughter. WHY WOULDNT I WIN????????? PLEASE HELP ME:(!
The father has filled a motion for TEMPORARY RELIEF to establish visitation- he states that I have harrassed him. Court is on Sept 24, 2008. HELP!!!!!