Hi Rachel,
I have had strong anger issues for quite a long period of time. I worked on it through many methods so I couldn't say there is a recipe for getting it under control. I will just say that what I learned is that anger is not an emotion. It is a reaction to an emotion you are currently unaware of. You can start with trying to identify the real emotions boiling underneath.
Once you realize what they are, work with each of them. This will help lighten the load you are carrying.
For me, what did the trick was realizing how much love I still had for the very same person who took the life away from me, my father. It's still hard to think of this and accept it, but it gets easier each day. And in the meantime, I have no more anger issues. Yes, I get angry from time to time, but who doesn't? I just don't stay angry and don't get angry because of the smallest issues.
If you are in therapy, I would advise you do this work with your therapist, as you could need grounding while working through these emotions. But you could also give it a try here if you want. You are not alone.