I really do feel for you. You have come to the right place! We will help you all we can. I agree entirely with what Justbgood says, spot on in my opinion.
I can relate to every single symptom of yours although I did not have suicidal thoughts but I was suffering from quite bad Depression because my symptoms were VERY aggressive. I also had chest pain which I have to say was quite scary, I'm only in my 30's and have had really good health until just over three years ago. I don't want to worry you but it has taken me up until now to just begin to get my health back. I believe I have been suffering from an Ascaris infection, I am a million times better but I believe it has taken numerous parasite cleanses to get as well as I am today.
I went private as my GP would not entertain the idea of a parasite. These are "rare" he said and people don't really get ill with them. GET REAL I thought. Never went back. I self-diagnosed myself, just KNEW it was parasite related. Itchy bottom, rashes on abdomen, biting sensations etc., the list went on. I have to say that many of your symptoms relate to parasites. Educate, Educate, Educate, that's all I can say, read the posts here on curezone, we are here to help, you will get well through this site. I'm not fully well but MY GOD I'm 100 times better than I was even a year ago. I'm not saying you'll take as long as me to get well, everyone is different and it depends on the infection and how badly infected you are. Do a parasite cleanse, (I tried many here in UK, crap products, found Humaworm (www.humaworm.com), I did a 30 day cleanse and got results. I still have symptoms, but not aggressive symptoms, I'm still infected and am due to do another cleanse at the end of January. (You need to leave a 90 gap before doing another cleanse so as not to create super-parasites, this is a real risk, don't let them get resistant to what you take, this happened to me and it got me in a real mess, through bad advice I have to say). Humaworm, I have to say, is the best product I have tried.
I purchased a zapper to help with my symptoms, it is a great piece of equipment, perhaps you could look into this also. There is a Zapper Forum here also, read some posts and decide for yourself.
I wish you well and I'm sure you will begin to see results and feel better once you start cleansing.