I think doctors like to grab any easy answer they can so they will latch onto any depression episode and blow it way out of proportion and claim all the problems are depression. I finally went to a psychiatrist and had a full mental health exam done because I was sick and tired of being told it was all depression. Even after the psychiatrist said I had physical problems my doctors tried to blame depression. I stopped telling them my mental health history but it changed nothing. Then I got health insurance and was able to see a rheumy. I told her everything. I took pictures of my rashes and a good summary of all my symptoms since my early teens and my health history. I also took a decent family history considering I have no clue who my biological father is/was. My case was really bad by this point and I walked out with a dx and tx. But I still have mental health issues. Chronic pain causes depression and I have a past that I have been told would have broken most people and left them without a scrap of sanity. I ended up with PTSD and a debate over if I have bipolar type 2 or if they are misdiagnosing PTSD symptoms as bipolar disease as my only manic episodes occured on extremely high doses of anti-depressants. My signature gives a very short outline of the health issues. I nearly died a few months after my rheumy dxed me due to inflammation in my gallbladder (years of inflammation) shutting it down and the ER doctors blowing me off because they didn't know my rheumy, she works out of a hospital 20 miles from my home but all my research and the lupus patients in my area said she was the best for lupus. She has been wonderful and saved my life by telling me what hospital to go to and what test they needed to run.
Unfortunately there is no magic key to make doctors listen and believe. You need a doctor who cares and who is willing to suspend disbelief and not assume depression is the root cause just because you had problems with depression in the past. It is ionic, when I am sad I cannot cry but when I am frustrated and PO ed I cry easily and have always been that way. I just do not process emotions like everyone else because of my past.
That said, you may have depression because of the pain and the lack of anyone who listens and believes you. If there is depression it can actually make things much worse and lower your pain tolerance levels significantly. I am not in any way saying depression is the cause of your problems, rather that depression can be caused by your issues and that it can make it much worse.
I have a horrid time with medications and side effects. I can honestly say neurotin (sp I am spelling by sound here) can help significantly with chronic pain and has fewer chances of side effects than other meds. I can never take another antidepressant because of my brain chemistry and how it reacts to having my neurochemicals messed with. I am allergic to most antibiotics. I suffer extreme pain on a daily basis. I spent years in therapy and for a while it helped but after a point it became more punishing than just letting it go because the therapists always want you to re-hash what bothers you over and over.
I find keeping your mind occupied can help with chronic pain. I am in grad school which keeps my mind busy and may provide the skills needed so I can work again some day. My cognative function is off lately so I likely make little sense but I guess the gist of it is doctors can be idiots and because they hate admitting ignorance or lack of expertise they often latch onto any simple answer no matter how idiotic. Pain, suffered for any length of time causes depression and even mild depression makes pain worse and adds to fatigue. You need to find the right doctor and have a thorough medical history and family history as well as a symptom history that has a fair amount of details. Yet you need to make sure it is not so much information that the doctor cannot process it all and feels like they have been swamped with it. When they feel swamped they tend to assume mental health issues like they do when they haven't a clue.
When you find a good doctor you will know it and trust will happen. Do not trust easily because this is your health, your life, and your future on the line here. Some doctors will listen and believe but make your symptoms fit their preconceptions or what they want to find wrong. I wish you much luck. I am under the care of the best in my area and I have still encountered serious issues dealing with GP's and PCP's as well as specialists in other areas (dermatologists, GI docs, neurologists, etc).
A solid mental health eval can dispell the assumption depression or mental issues are the root of your health issues and if depression is an issue can offer safe treatment that will force medical attention back onto the medical problems. Also mental health medication should be prescribed and managed by a psychiatrist and not by any other kind of doctor. This is from my rheumy who says the meds used for mental issues be it depression or something else are too easy to screw up and that too many unqualified doctors are assuming they understand mental health issues based on the short section from medical school and prescribing these meds when not needed or incorrectly. Only a psychiatrist can accurately prescribe and manage them and even they make mistakes at times but at least they know how to fix it when they screw them up.