I could really use some support...

Alright. So I've never really done anything like this before, so I'm not sure what exactly what to say, but let me start by telling you a little bit about me. My name is Heather, and I am 18 years old. I am 5'1, and I currently (as of this morning) weigh 186lbs. I have tried and tried again to lose weight, but I can never keep up with it. I always end up having to give up.
Let me elaborate a little bit. When I was 13, and 14, I went through a time in my life when I was an on and off anorexic. I wasn't really that big at this point (only bouncing between 140lbs and 150lbs). But even at that weight everyone around me would make fun of me, and tell me about how I need to lose weight. My dad would buy me the "fat free", "sugar free", and "low calorie" version of everything and tell me I couldn't have the normal version, because I needed to lose weight. I would go up a pant size because I would be growing (like any other teenaged girl) and instead of buying a bigger size of pants, my dad would tell me it's "cheaper to lose weight". He still treats me like this all the time. I can never hear the end of it from him.
I also, as you can imagine, have a great deal of depression and anxiety. Now a days it's more anxiety than depression, but it's still practically crippling me nonetheless. And then of course my dad will yell at me for being lazy, when in all reality I legitimately cannot bring myself to get out of bed because I'm suffering from a panic attack some days.
Now, I never really got over my eating disorder, I just did a complete turn around, so I began to overeat, and binge eat all the time. This turn around, combined with my hypothyroidism caused me to gain a great deal of weight (about 36lbs at this point). And of course I'm not happy with how I look now!
I keep trying to lose weight, but every time I set up a diet and exercise plan for myself, I end up obsessing, and taking it to the extreme and scaring myself.
I will start out with a relatively healthy plan. Eat 1,500 calories a day, burn 300 at the gym, and be left with 1,200 for the day. Not too bad. But then it would turn into, eat 1,200 a day, burn 400 at the gym. Then eat 1,000, and burn 500, and so on. Every single time I end up back in my anorexic mind set, eating no more than 200 calories a day, and making sure I burn off at least 500 everyday. And if I don't adhere strictly to that plan, I have panic attacks and beat myself up about it to no end.
So, I keep telling myself that I'm not allowed to watch what I eat. If I don't think about what I'm eating, it can't bother me. I eat whatever I want, I weigh whatever I weigh, and that's it. But I always end up realizing that I'm not happy at a heavy weight. But of course, I'm never happy trying to lose weight either.
I'm tired of beating myself up over my weight. I want to lose weight so bad, but I'm so scared of falling back into my super unhealthy routine.
I just can't seem to be happy about what I'm doing, no matter what I'm doing! I always find a reason to beat myself up!

But. I've decided that I'm going to give it one more shot. I'm going to try and keep a healthy diet, not too few calories, and not too many. I'm just still apprehensive about getting out of control again. That's why I'm reaching out to my fellow dieters. I just want some people to help support me, be my friend, and help me stay on a healthy track. It would really mean a lot to me. I'm hoping that people supporting me will be just what I need to make this happen.
If anyone wants to help me out, I'd really appreciate it. And even if you don't want to, thank you for reading