Lost Faith

I'm struggling with my faith in my life right now. I'm actually doubting whether there is a God or not. When I was little, I KNEW God..in fact I wanted to be a nun and do charity work for the Peace Corps. I've had many low blows the last three years..losses...my mother, who was my best friend, 4 of my animals (they are my babies and have been with me a large part of my life), my job (I've never been fired and NEVER not worked!)....I've lost touch with my dearest brother, who may be living in the streets..(He occupies half of my hear)....
Each one of these "challenges" I took bravely and tried to move forward..I tried praying, but it feels empty when I do. I dont understand what's happening. I also just turned fifty (in July) and might be having peri-menopausal symptoms, which is adding much to my state of being.
Throughout my life, I've always been happy, never depressed. I LOVE people and LOVE giving. I just dont understand why this is all happening to me at once. I'm so discouraged.
How can I get back that warm comforting feeling of knowing that God will handle everything?

Mary