Health decline-have to lose weight now!

Hi everyone, let me tell u a little about me. I'm new here, so I'm trying to figure out the ins and outs of things. (Mainly, I, with much anxiety, tried to post "before" photos of me to start my progress, on my home page thing, but after uploading the first, when I tried to upload more in the next status, it just goes automatically to the first I uploaded, and I don't know how to change that) Anyway. My name is Krissy. I've been married for almost 5 and 1/2 yrs to the the most amazing and wonderful woman I've ever known in my life, Melissa (u will see me refer to her by nickname, Missa). We have no children, but two furbabies, a cat and dog, both will be 7 this year. I'm the oldest by 6 years, of two, and my sister had her first baby, my nephew Jaxson, 2 years ago. I'm 34 years old, and will be 35 in September. I've been through a lot in my life, from my teen years til now. I was officially diagnosed with depression when I was 16. I always had trouble with my womanly cycles, and was diagnosed with PCOS shortly around my 19th birthday. I was a size 8 in high school, until, in one year alone, I went all the way to an 18. (Obesity goes along with PCOS.) I've struggled with my weight ever since, major self-esteem problems, I would lose 30-40 pounds, then gain it back...yo-yoing through the years. I had to have a hysterectomy in 2012, and that along with the weight added to my depression. I've recently went from 256 pounds to 220, what I am now. I'm terrified to gain it back, but I'm not losing anymore either. My lower legs are bowing due to my weight, I have major arthritis in my knees and my lower back and tailbone. I have problems with my heart, and am at a high risk of a stroke. My cholesterol is also out of control. I need to lose this weight. I have zero willpower on my own. I've also been diagnosed with bi-polar disorder, severe anxiety disorder, and PTSD. With a lot of things combined, I don't handle stress well at all, and so I eat. I am probably an emotional eater. I have a hard time with my blood sugar dropping too low if I don't eat enough or the right things, so I am always at a loss as to what to do. I guess its just really really nice to have a community here that I've found that have weight problems, and goals like me....so, that's my story...there's probably more, but this is just one chapter lol.
Thanks!
Krissy