1) Strengthen your "mind muscle" through meditation or mindfulness practice. Meditation is not "making your mind go blank"; it is focusing and calming the mind. The mind is like unruly horses, once you are in control, you can direct the mind where you want it to go. Otherwise it runs away with you (and often into flashbacks). This is the single most powerful aid to healing PTSD.
2) Eat whole, nutrient-rich and easily digestible foods. Our digestion suffers tremendously when we are stressed. PTSD is whole body event that depletes our energy and nutrients. Cut back on sugars, caffeine and alcohol that tax the body and especially your adrenals.
3) Find ways to safely tell your story, even if it is in a journal or through art. Finding your narrative and being heard are immensely healing.
4) Safely release held feelings. Crying is necessary, and sometimes so is shouting. Go fight with the ocean waves, run, hit a ball, or watch a sad movie. All are helpful. Holding intense feelings in becomes toxic over time. So release!
5) Learn to comfort yourself. You have been deeply wounded. It is OK to focus on yourself during this time of healing. Comfort is always healthy and never creates further problems. In other words drinking alcohol is not comforting but avoiding. True comfort involves activities like: being out in nature, taking a long hot bath, getting a foot massage, listening to your favorite music, redecorating your space etc. If you need to wrap up in a large blanket and stare off into space, that's OK. Balance comfort with necessary activity.
I feel for you and your suffering. I hope this helps!