Hi Missing...
If you read Codependent No More by Melody Beattie, you'll think she wrote it about you. You may get more out of a CODA (Codependent) meeting if there is one near you but Al-anon will help. Try this web site to find a meeting.
http://www.codependents.org/
Just from what I read in your post, you're really codependent and take on everyone else's burden's until you're staggering under them. If you don't find some middle ground and let others take some of the responsibility from you, you may find yourself with major health problems.
Just for today... do something nice for yourself. Take a walk, take a bubble bath, or listen to some nice soothing music.
Try the web site and keep posting. We care...