Sadness after miscarriage

I'm posting this in case someone else feels that way or has felt that way,  I've had a miscarriage a month ago and although I'm generally an emotionally strong person I just can't shake off these feelings sadness, anger and unfairness that I've been carrying around. I'll be going through my day and it'll sneak up on me in an instant. My fiancé is super supportive but I'm wondering when I'll feel like my old self again, I haven't felt grief to that extent before and frankly I am both impatient and terribly frightened to get pregnant again. I can't always burden people with my grief .