I need MAJOR help!

My name is Tori. I am 22 years old. I have been overweight my WHOLE LIFE.. I don't even know what it's like to be skinny. Ever since i was in the 2nd grade I was always chubby. Ever since i graduated high school I have gained 50 lbs. My mini goal right now is to get under 200 lbs.. but over all i want to get down to 150 or so. I NEED HELP.. i don't know what my problem is. I have tried many diets.. and sometimes im really motivated but MOST days i'm not. Which i don't understand how i keep fooling myself because i want to lose weight MORE than anything! I was thinking maybe this site would help if i had some kind of support. I don't know.. but it's worth a try.