Lovely images, and well told such that I could easily imagine myself dropping in the water with her.

I think the last line should be connected with a comma to the sentence before it. In the first paragraph you use ‘together’ twice; consider an alternate word choice for one of them.

Very nice feel to it, and I liked the sense of aloneness in a positive way, both scuba diving in general and in the contrast of how your character is to the group of divers to their left.

beautiful, serene, and peaceful. Thanks, I needed that!