Hi welcome to the boards though I am sorry for your pain. I can relate to a lot of what you are feeling. I think for me and this is easier said then done but I try to stay in the day. The worry of the future is just too much. I am going through a very bad time right now pain wise and mentally it really has hit hard as well. I try to remind myself of the people I have met who after years of being in a bad place with the rsd got to a better place and have a full life. I think it is just about finding the right treatment for pain relief which is different for everyone.
It is so great you have family and friend support. Trust me though I understand how you feel about them not understanding. I think that is why this forum is such great support.
Hang in there