I need a beginning for my story?

start by telling of the past.. Mary was walking in the park, the only place she felt free. She would look at the flowers to try to rid her mind of the past.... Then give a picture of what she is trying to forget, or a picture of the flowers, watching the bees going from flower to flower, or humming birds or such.  Then you can bring in the new friend.

This worked for Charles Dickens:  “It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, …”

The main plot of the book is about a girl who is struggling her way through love. You see. She doesn't know what love is because she's never seen it before, growing up. Her dad was a drunkie and never did anything but sit on his ass all day and smoke pot or something. Her mom got sick of his lazy behaviors and kicked him out. Later in the years her mom somehow grows into a drug addict herself and stoPS paying attention to her daughter. So basically all throughout this story she's trying to find the true meaning of love. A boy about her age meets her in the most unexpected way. At a park, he sees her and he talks to her. Throughout the story he begins to talk to her, he shows her love. He tells her all the things she needs to know about love and so on. I wrote the prologue. But I haven't gotten stared with the actual chapters yet. Writer's block is killing me. I have not come up with any ideas or solution for my story. I know where it's going, but I don't know how to start it off. Please help. Thank you so much I would really appreciate it

Once upon a time.

In the beginning....

Or

It was a dark and stormy night.

Or

Call me Ishmael.