I'm so sorry to hear what you are going through. I am going through a similar situation. I was diagnosed with Chronic Migraine exactly 3 years ago. I am 26 years old now. I have not had one headache free day since I first started getting them back in October of 2012. I have a constant 24/7 headache that escalates into a full blown migraine at any second. I have tried every major medication they prescribe to people with migraines. Proponalol, Topamax, Amitryptaline, etc. I have tried Botox, nerve block injections, 5 day DHE hospitalization, nasal sprays, triptan injections, preventative meds, patches, Cefaly, acupuncture, physical therapy, chiro visits etc.
I am at my wits end. I regularly follow-up with Johns Hopkins Migraine Center in Baltimore, MD. They recently prescribed me Namenda. I have been on that for about a week now. I have not noticed any changes yet. I have also been on the Paleo diet for over a month as a form of food elimination diet, since I've tried other migraine diets before with no success. Johns Hopkins told me that Namenda is one of the "out of the box" meds to try since I have tried almost everything they normally give to migraine sufferers. I really hope that Namenda works. They suggested another med, another out of the box thinking pill, if Namenda doesnt work after 6 weeks. I guess we will see what happens. I'm glad to hear that Namenda worked for Merry (above). I'm sure they will be able to find something that works for you. Don't lose hope.
I wanted to reach out and let you know you are not alone. Hang in there and we will all find something that will work! :)