Well, it does sound like you are in place where you need help in order to preserve and/or restore your level of functioning and your quality of life. It sounds as if you do have what would be diagnosed as "panic disorder", though I am just going by your saying that you have chronic anxiety about having panic attacks, which you do, in fact, have. Panic disorder is a bitch; I, thankfully, have never been in a place where I was having anxiety about having a panic attack, which is what usually defines panic disorder, although I have had a few isolated panic attacks in addition to my anxiety issues, so while I cannot understand the full range of your type of anxiety firsthand, I do have an idea, and it must be pretty shitty. I, also, have a very close family member who suffers from true panic disorder, and I have seen how it can really tear someone apart. You say you also have problems with your sleep, which sounds from your post like chronic insomnia; that must worsen the anxiety even more, and I'd guess it is the anxiety, to some degree, that keeps that cranked up. So, I do really feel for you, not that I know chronic insomnia, personally or firsthand, but I do know how awful chronic fatigue can be, and I know that firsthand.
As for help, that I might recommend you look for, and at this point, it does seem quite obvious you need more help than you're getting, I would recommend, firstly, really informing yourself about the different techniques used to treat chronic anxiety, in general, as well as panic disorder and individual panic attacks, as well as chronic insomnia. I would honestly recommend you get to know the different types of treatments, with respect to both drug therapy and all other forms of therapy, formal and informal, of eastern and western medicine, so that when you do get help, you'll be a patient who could actively participate in your own treatment. It really is true that one must be one's own advocate and one's own source of knowledge when receiving treatment from doctors, especially, and other professionals you might benefit from, too. It is a pity when a patient goes into a doctor's office and blindly follows a doctor's often subpar, and even often very poor, advice and suggestions. I don't want to scare you away from doctors; I just am emphasizing that going into a doctor's office prepared with knowledge is going in so much more likely to realize if the doctor is a good fit, and if he or she is steering you in the direction in which you want to go. Knowledge really is power. I know that from personal experience - believe me. But, it seems you ought to start looking for a medical doctor or doctors to help treat your anxiety, panic, and insomnia. The anxiety and panic would be treated by a psychiatrist, if you want to try drug therapy as a means to help your condition, and the psychiatrist would probably be the same doctor to help your sleep disturbance, too. But, go into a psychiatrist's office knowing, yourself, what he or she could do that you would be okay with and that you wouldn't be okay with, too - again, study up and learn about your symptoms, possible diagnoses, and particularly possible treatments, including pharmaceuticals available. Now, I wouldn't go into such a psychiatrist's office and tell him or her you want a, b, and c - that won't get you far, but telling him what you have taken before, how it has worked out for you, how you really cannot function now on account of your anxiety, panic, and insomnia, is perfectly fine - a patient should inform his or her doctor of all that. I will say that good psychiatrists, and doctors on the whole, seem to be few and far between, so sometimes you have to have a consultation with another, if you didn't think the first was all the great, and you might have to do this more than once - I don't know. But, it does seem worth it to seek out help at your point, as you've described it. Like I said, just study up, don't let yourself be naïve, ask good questions, etc. And, learn and practice self-relaxation exercises that you can do simply by yourself, including meditation. Someone mentioned yoga; it is a truly wonderful thing for the anxious person.
Now, as for a bit of knowledge/input to share:
Benzodiazepines like Valium (diazepam), Xanax (alprazolam), Ativan (lorazepam), and Klonopin (clonazepam), to name a few of the more common ones, are sedatives which are commonly used to treat anxiety-related problems and different types of insomnia, too. Sometimes, a GP/family doctor will prescribe a small supply to help you until you see a psychiatrist, sometimes a GP/family doctor will prescribe you this type of drug, regularly; it is less common, it seems, than GP's will do this, but I know of cases where it is so. Really, though, it is in psychiatry where these drugs are most comfortably prescribed for anxiety and insomnia (I am grouping panic into anxiety, for the sake of this part of my post). But, you will even come across psychiatrists who feel you have to try seven different anti-depressants before they'll put you on a benzodiazepine, or will put you on an anti-depressant and give you a small amount of benzodiazepines to start out with, or will give you only a small supply of benzodiazepines regularly but only for P.R.N. (as needed) use. Other psychiatrists, while still almost always starting with an anti-depressant, will agree to a round-the-clock benzodiazepine with a bit more ease. The reason I am writing on and on about this is because you said that you have tried many different anti-depressants with no good result, your anxiety and panic are very severe, and your insomnia is seemingly very severe, too. To me, it seems you might feel much better with a benzodiazepine as a part of a drug therapy regimen, perhaps only as needed, perhaps around-the-clock, perhaps both, and perhaps any combination of that and an extra something in the benzodiazepine family to help you sleep. Usually, if you are on a round-the-clock benzodiazepine, your sleep will be helped as the drug will be exerting its anxiety-relieving effect and sedating effect at nighttime, too. Honestly, I cannot say, because I do not know enough about your particular situation, how you would want to approach things, and that type of thing. You do have to be aware that benzodiazepines will produce physical dependence if used round-the-clock for more than a couple weeks, and when they are prescribed to you like that by a psychiatrist, it is expected - in fact, it is known that it will occur within a fairly short time. And, it is true that coming off benzodiazepines is a long, hard, and drawn-out ordeal, BUT they can really, really help anxiety, panic, and insomnia, and many people swear by them for years and years. So, there are pro's and con's to them, and the same goes for the fashion in which they are used. It might be that you only would need something at bedtime and something to use as needed, in addition to other non-drug therapies such as simple talk therapy with a psychologist or counselor or someone like that. Another thing to mention, just because you are really suffering from panic attacks, is that Xanax (alprazolam), even at relatively low doses, can be a VERY good option to use when the actual attacks occur, for it works very well and very swiftly. I'll mention, too, that Klonopin (clonazepam) tends to be the best for preventing panic attacks in the first place, and for helping general anxiety of the nature you are describing. I am not saying those are the ones for you, but I am saying they might be considerations.
Neurontin (gabapentin) and Lyrica (pregabalin) are not commonly used in psychiatry in the U.S., however it seems Neurontin is being used more and more to help with mood stabilization/regulation. But, these two drugs do help anxiety and insomnia, and probably, on the whole, just as well as a benzodiazepine would, given you are taking either one at a sufficient dose. Both do cause physical dependence, as well, however, like benzodiazepines. And, as with benzodiazepines, one does become tolerant to some of their effects to an extent. They aren't as feared by a lot of doctors that might be hesitant to prescribe a benzodiazepine, however these two drugs are mostly used for pain conditions and epilepsy, but not always.
I could go on about all of this, but I will leave as it is for now. I may add more, later, if I think of anything that could be particularly helpful.