I've been thinking about this pic somewhat since it first came out, and I believe I've discovered deeper meaning in it.
This work is like a microcosm of Zoey and Fiona's relationship with each other; Zoey is completely open to her partner, every feeling pure, and coming straight from the heart. Fiona is caught off-guard by the incredible wealth of feeling that Zoey has for her, and reciprocates awkwardly, struggling to respond in a manner that conveys how much she cares about Zoey herself. Zoey sees Fiona's struggle and doesn't care. She knows that Fiona loves her, regardless of how she shows it.
I dunno, maybe I'm seeing depression where there's just blue curtains, but it makes sense to me.