Answer:
Dear X,
How have you been? Is everything great?
Well, I'm having a big party at my house this weekend and I would like to invite you. I promise it will be fun. All of our friends are coming. We will have a lot of fun activities together. Also, my grandma is going to make her famous apple pie which you love.
My house is next to the antique shop, 15 Hornby Street, just in case you forget.
I'm looking forward to seeing you.
With love,
(Insert your name here)