I am certainly not a therapist and can only speak from my own expereince, but I know that the thing that started my journey to acceptance and healing was when I recognized that there are no shoulds in life. When we focus on how things "should" be we get stuck, because when we look at things they are definitely not how they should be. If we are powerless to change them, then we will stay stuck forever in the place of what should be but isn't. When I let go of my ideas about how things should be, and accepted that life is strange and doesn't always turn out the way we think it should, it was the beginning of my journey toward healing and closure. Still a long journey, but much better than staying stuck forever!
I wish you all the love, support and healing that you need. I hope I've helped even a little.