2 years ago I could have written your post OP (in fact I probably did!). I'd had an accident, multiple surgeries, probably depressed, weighed about 16 stone.
I got a lot of help on here to start valuing myself right now, in this moment. I got a haircut, waxed my brows, learned how to give myself a decent manicure, bought some clothes that fitted me and looked nice, rather than buying anything from the men's department of mountain warehouse that actually covered me. I decided not to worry about my fat at that point. I also went back to the GP and insisted on a pain clinic referral. At that point I was on morphine patches, rescue tramadol, naproxen and god knows what else, and I was STILL in pain. The pain vlinic wasn't a magic bullet, but they helped a lot. Over time I sent the wheelchair back, reduced the crutches and eventually moved to a single stick. My simple rule in the early days was that everyday, no matter how bad I felt, I put on earrings, perfume and mascara. It sounds trite, but it helped. As did having a few nicer things to wear. I started to feel that there was hope.
I didn't feel able to begin to tackle the weight issue till early this year. I joined the LCHF bootcamp mentioned above by Kleptronic, and I've since lost 50 lbs and still losing. About 6 weeks ago I felt able to risk more vigorous exercise, and started a C25K programme, and this morning, I ran my first non stop mile :)
The point is though, that first of all I had to learn to value me. Rather than hating myself for how I looked, I had to accept and celebrate my poor broken body for surviving. I had to accept that bring fat wasa coping mechanism rather than a moral failing. So I was in a mess for a long time, probably took a year to do the mind stuff, and have spent this year working on the physical (which of course brings up more mind stuff, but that's another story!). I'm also quite a bit older than you, so it's never impossible to change.
Good luck, and do come and join us on the bootcamp if you feel it might be for you. But whatever you do, start being kind to yourself :)