A sweet and short dream to tell your girlfriend could go like this:
"I had the most delightful dream last night. In it, we were sitting on a sandy beach, holding hands and watching the sunset. The sky painted in beautiful hues of pink and orange mirrored the warmth in our hearts. With each wave that kissed the shore, I felt even closer to you. It was a dream that reminded me of how lucky I am to have you in my life."
This dream evokes a romantic and peaceful atmosphere, focusing on the connection and love shared between you and your girlfriend. Feel free to personalize it with details that are meaningful to both of you to make it even more special.