Sorry to hear that, its always hard losing someone. I imagine it must be especially hard losing your father. Heartbreaking to hear about the trip as well. I know from personal experience it adds an extra layer of bitterness towards the unfairness of losing them so suddenly with something to look forward to.
I wish you the best with your grieving process and hope that you have some support network around, and if not and you simply wish to rant, I'm certain you have more than a couple ears here.