Piece missing?

I think I'm ok. It's hard to tell. The big picture is I'm fantastic. I have a home, a job and the perfect son and we have our full health. But in the microcosm of that bubble I wonder if there's a slight turmoil building. 

I've not drank alcohol for four years three months. But last week I did have six non alcoholic beers. I've also had moments of imagining being in a relationship again. But it would be such a perfect relationship that it's a thing of pure fantasy. 

My trouble has always been that when everything's ok I introduce the one thing which will spoil the quiet. I just want a quiet life. 

I have the quiet life already, so what is this niggle that suggests I'm missing a piece of the puzzle?