Oh Dee. I know your family are so important but for once you really need to think about yourself. It sounds like you have had a horrific time and you have done so well to get through like you have.
I think a visit to your doctor would be good and then you can go from there. If you can explain to your family how you are feeling, they may understand but I know that might be quite difficult.
When someone dies so suddenly its the hardest way. I lost my best friend that way. She was murdered. It is hard when you can't say goodbye. Im so pleased that you had such a good relationship with your dad, it will help you to remember the good times you had together.
He would be so proud of the way you have held your family together and that you have been so strong. Please try and take some time for yourself, to get well and to grieve.
You are in my thoughts, I really do think you are a wonderful strong person
Take care x