Hi Annabel123,
Grief and sorrow are hard to bear. I found some good books over the years and found it helpful to read about grief and other people's writing about their grief over someone close to them dying. I think the main theme of those books was that this is an emotional process that has its own timeline and the people worked to accept where ever they were at that day, even that hour, or moment to moment.
I agree with Matt, if you reach out, you might be able to connect with someone who has processed grief in their life and they may be able to be there for you in some way right now. I would just add that if you are with people who invalidate your grief, it can be the opposite of helpful. Not everyone is comfortable with grief or have skills to be comforting.
My understanding or perspective on grief is that it is not a negative emotion (the way anger is) but it can get labelled as such because it hurts so bad, and because other people might want you to "perk up" i.e. do not understand / accept your grieving process. It relates to our connections and attachments we had with what we lost. As we go through grief, we gain wisdom and experience that someone else might need from us at some point in the future.
Have you tried any exercises to give your grief a voice? There is a lot written about how drawing , journaling, making art or doing something to give form to your grief, even if no one sees it but you.