Yeah, it's definitely possible but climbing feels like the ideal sport for couples.
Going climbing together builds a very strong bond. You essentially trust each other with your lives since you belay each other. So it makes sense that I mostly saw couples in the climbing gyms.
When we did our top rope course together, we were the only ones who weren't a couple.
I also liked the security aspect of it. Every time before someone goes on the wall, you make sure they are secure with absolutely zero compromises.
Maybe that's one reason why I like ~security so much. Lives can depend on it :)
Damn I miss climbing lol