I want to fit into my White Skirt!

Hello Everyone,
My name is V and my weight is currently 206 and I am only five feet. I have been trying to eat better and work out since November of last year. I have a bad cycle that I am trying to break. I will start eating better and exercising more and then I blow it and I start to eat and gain weight. Then I do this all over again li guess this is a clear and cut definition of insanity. What I notice is that sometimes I make unrealistic goals and then I get disappointed in my self and I quit. What I am trying to do differently is set realistic goals and change my ways. Like I am no longer dieting, but I am changing my life style to include healthy eating. I was not always like this in fact when I was 18 I was a level 9 gymnast with killer legs and abs. Now at 32 with a full time career, and a family I have let my self go, and it is no ones fault but mine. Although for a while I did blame it on my son, but now that he is over two years old I think that ship has sailed. The weird part is that I never noticed it in the mirror when I looked at my self I looked good, I think I had beer googles eye... hummm..I don't drink beer so not sure how it happened. I did see it pictures and I hated taking pictures, but I'm sure like many of you I have mastered the art of picture angles to make me look skinny. "Got to LOVE those Selfies!" I bet everyone is wondering why I am sharing my story? The reason why is I think that if I tell my story then I won't be ashamed of myself and it well help me reach my short term goal and long term goals. My short term goal eat better be more active and by my birthday at the end of the year I want to be able to fit into my white skirt and travel to the Florida Keys! Which is a Large and I think like a size 16. I am an 18 possibility 20 not really sure, it's a small goal and I want to lose .5 pounds a week. If I can do that I think I can fit into my shirt... Here We GO! ...Let's Get It Girl!