I've really had to work through a lot of pain and trauma from my childhood as well. I've been working with a therapist for about five years. I've only had about 3-4 sessions this year so that's definitely tapered off for me. I think I've felt better this year than any other. I don't think I've experienced any episodes of depression either, at least none lasting more than a day or two (used to be months at a time). Hopefully I can give at least a few suggestions that may prove useful to you.
I think the main thing that accelerated lasting change for me was learning that I had a choice as to where I could focus my attention. Steve's post on
overcoming depression talks about this at length (as does many of his other posts). I switched from constantly focusing on my past life situation, current negative situations, etc. to focusing on what I want in the
present. I began putting my intentions toward feeling good, not sometime in the future but right now. I stopped putting myself in a negative emotional loop by constantly thinking about my "bad" past or present situations. I just accepted what happened...and what is.
This is definitely a work in progress. I still get "triggered" which tends to wake up my "pain body" (as Eckhart Tolle puts it), which may be like what you're talking about in that your body hangs on to this past truama - it's your "pain body". I have really been working on bringing my attention to my breath and my body at this time and not going "unconscious" (or on "automatic pilot" as my therapist would say). I've found that staying very conscious and focusing on my breath or on my body really helps. I guess you could call this meditation. By doing this I stop my mind and pop out of "psychological time" (i.e. ghosts of the past or future fears) and into the present (which in doing so is the only time I've ever felt peace).
This doesn't really seem to take long. Last night, for example, I started feeling anxious and began searching for something to medicate myself with (the start of my usual "autopilot" procedure). I even began walking to the store to grab some goodies! On the way there, I decided I'd just focus on the present during my walk, as I've described above - sort of a walking meditation. Something just seemed to nag at me to do so. Minutes later I felt fine. This may not sound like much but is huge for me! I was able to sit with my pain consciously and not medicate myself. Within minutes this pain was "transmuted" and I went to bed feeling perfectly at peace. It wasn't medicated and stuffed back down to multiply and come back worse at a later time!
I'm sure a lot of the anxiety and other negative emotions I feel during these times could be traced back to a past event, but I have found doing this is just not effective. Doing this in the past has never really brought me lasting change. I don't think we need to uncover every single trangression and feel every single negative emotion attached to those transgressions to be able to be at peace. I think you could be in therapy doing so for a lifetime. Perhaps this is why the process of psychotherapy seems so slow! This doesn't appear to be necessary to me. I think we can be at peace right now.
I think what's really worked for me then has two basic parts. I focus on what I want and I work to maintain a conscious awareness on my breath and/or body, especially when I'm feeling pain. This may seem overly simplistist but out of everything else I've tried, these two actions have helped me the most.
This is the first time I've ever elaborated on this so I hope it makes sense!