So sorry you're feeling so bad.
Don't give up. I haven't read your other posts but I do see you've posted on the PN forum. Please keep on looking for some answers and some relief for your physical pain whatever is causing that. Bad physical pain is enough to cause people to want to give up.

I hope you are not alone and have someone - friend or family - who you can talk to about how you're feeling at the moment. If you are alone, please call someone to come to visit you and just be around if you're feeling like you want to "check out".

What to do if you are alone and thinking about suicide.
http://neurotalk.psychcentral.com/thread4982.html