I haven't had to deal with chronic pain myself but (as a naturopathic student) I would like to add to Bec's excellent list of suggestions lots of good quality high dose Fish Oil. The essential fatty acids in them are not only excellent anti-inflammatories but are also involved in the mood hormone pathways so will help aleviate depression . You should start to see results for inflammatory pain in a couple of weeks - mood takes longer.
Please see a specialist health store and don't go for those cheap brands with the enormous packages - you need to take 10 of those a day to get anywhere near the dose you'll need so it won't be cost-effective.
Good luck - I really hope you can get on top of the pain without returning to the Endep