why am i so fat??

OK I am new to this, but maybe as I post, I will learn something new about me and it will get me going. I am 42, and have been married 23 years, we have 2 boys.As a teen I was anorexic, had lost down to 100 pounds and felt good. I got married and well things just grew!! Especially me, but he did too. Right now I weigh 270, more than most of the guys I work with. I don't think of myself as fat, until I catch a glimpse in the mirror and then I am mortified!! I think sometimes there is something wrong, but have been tested for thyroid etc. I am always sleepy/tired, but I work a LOT, plus I go to school full time. I LOVE food. Maybe sometimes I eat for fear that we won't have anything to eat the next day, somedays its just that its there and tastes good. We are struggling to make it day to day, I think back and say what could I have changed over these years?? What do I do?? What can I do?? I am trying to walk, but something always seems to get in the way. I don't want to be a skinny anorexic again, but I would like to actually be healthy......is that right to say? I am so clueless!