How to stay positive when bad things keep happening?

I am not trying to throw a pity party, but to give you an idea. Over the past year I miscarried my first baby, got sick and spent months and lots of money trying to find answers, my step-mum’s cancer came back and it’s spread throughout her whole body and there is no treatment option, my mother and I fell out, 3 different venues canceled on me for my wedding and this week my car broke down 2 days before I was meant to go away, and my dad was diagnosed with cancer.

I know there is good, I know. I’m getting married to the love of my life. My health has improved almost 100%. I have a stable job and a home to go to every night, but I just can’t seem to stay focused on the positive and all I can feel the negative and how it’s impacting me and my life. I’m scared for my Dad and my step-mum. I’m sad that my mother doesn’t care about me enough to even try. I’m still so sad about my baby and I’m scared to try again. I’m just in a black hole and I miss the sunshine.