I had a time in my life when I gained a lot of weight and just like you, I think I've tried everything… 1000 calories, South Beach, Atkins, you name it, literally everything. And as ordinary as it sounds, for me what worked best was just the plain, good old fashioned ,,eat less, move more" strategy. No specific diet, I just ate much less, started running, drank lots of water. And actually, when I stopped focusing on finding a miracle diet and started focusing on my motivation it just worked- I lost 20 pounds so far, 10- 15 pounds to go and I'm done! I realize it sounds like a lame advice and I remember how sick I was of hearing ,,just stop thinking about it, just find balance", but in the end, that was what worked for me, personally. I threw out my scale (it was only nerve racking to weigh myself!), I took up jogging and I signed up for fitness classes and paid attention not to eat more than 1400 calories a day.
I know it's not a mind blowing advice, but that's what helped me