What Causes Unexplained Bruising On The Left Side Of Body?

I am searching for information regarding unexplained bruising on just the left side of my body, from my waist to my ankle. I have recently started taking iron supplements, but it doesn't seem to be helping much. You can see fingertip prints on the left side of my waist this afternoon, and they were not there this morning. I am a 45 yr old white female, 5'4" 128 lbs, currently in good health. I am a domestic abuse survivor and have a history of clinical depression, but I take generic Wellbutrin and Cymbalta each day. I am no longer married to my abuser, and I am happily engaged to a wonderful man.