Hi Clara! First of all, I hope you may be feeling better by the time you read this.
I think there might be a few things that could help; maybe you'd like to discuss them with your team, since I'm no doctor, but the way you put it it doesn't seem they are doing that much to find the reason of such a higher level of HbA1c.
Now, you didn't specify what you eat or drink, but I think with those levels you should really go low-carbs. You know, like, one steak, salad, and just a piece of bread to keep carbs on your diet. And I don't know what you usually drink, but avoid soft drinks (even the "light-no sugar" ones for now) and alcohol. Just water.
No wonder you feel thirsty and tired all the time; your body is trying to eliminate the rest of carbs that are "over the level" through your urine. This much constant work will affect your kidneys in a long term. So, I think you shouldn't get that much carbs in your diet now, till you can lower your levels. Anyway, you said you have no appetite, so, if it is the insulin:
You say you use Humalog during the day, and Lantus at night. It's kind of weird now, because Humalog will just make a fast effect over a high level, and then after a few hours the curve will raise again to your standards if you are not using it alongside a long-act insulin like, say, Lantus; The insulin plan you currently have would only work (my guess) if you'd had a low carb diet, regular exercise, and normal levels to start with.
It can also happen that after all this years your body has developed a resistance to the medication, but it doesn't happen that often.
I don't know where do you take your shots, but you would like to alternate, for example, your legs and arms.
Another thing that helps me is to exercise the body part where I've taken the shot. It helps the insulin to act faster, and expand. Say, I play the guitar. If I got a level of 382 mg/dl. I'd take the shot on my right arm (the one I use to play rhythm) and I'd get the insulin to lower my level faster. In the other hand I'd avoid that arm if I'm going to a rehearsal and I got 142 mg/dl on the test.
Last but not least, Depression, stress, nervousness, it will just make your levels worse! And if they are worse, you'll feel more depressed and so on...
Hope something of this will help a little. Of course you should ask a professional.
I'd really like to hear you are doing a lot better in less that 2 weeks! I now you can!!