HeyThere,
Sorry to see your status but I'll answer anyway.
Sure DHA is a major component of Omega-3 oils and is very helpful for a good lipid profile. The same can be said for EPA. Major benefit is the ability to raise HDL but not to be sniffed at is the anti platelet clumping qualities...preventing blood clots.
Most on the board try for 1000 mg Omega-3's (N-3), the sum of DHA +EPA.
Fish oils however are a melange of different weight (carbon length) oils and even have Omega-6 oils like most vegetable oils and even some saturated oils.
I get mine from a tsp of cod liver oil a day.