I heard a good analogy the other day that sometimes trauma or grief is like a ball bouncing around your inner walls, and every time it hits you feel pain. Over time the room is still there, and the pain still sounds, but the ball hits less.
Sorry you gotta live this suffering. Perhaps see it as not something you hate or feel sad about, but just a feeling like any other in this rich tapestry of life. When it moves through you, welcome it as an old friend. Happiness is not the be all and end all, just another thread.
I do hope it fades with time. Have you ever received any kind of therapy?
I've thought of this bouncing ball analogy a few times since you mentioned it. Is it a bad sign that the ball is red right now?? I think that's a good way to have some hope for the long-term. Hopefully the ball will eventually lose its bounce as well and just roll into a corner.
I went to a therapist a handful of times. It did help a bit, but I don't think I feel I'll get more benefit from it at this point. It was helpful during the initial events and shock to make sense of things, but keeping it up doesn't feel necessary right now. However, I have that resource available as needed.