How do I get past this? See details.

A few weeks ago I met a girl, in one of the most beautiful places on Earth. She’s like no one I’ve ever met before, and I fear she’s ruined all other girls for me. We spent a few intense weeks together, but for reasons I won’t get into here, it doesn’t look like we’ll be together. At least not any time soon.

My problem is that since this drama, now that I’m back to my normal life, everything looks… grey. Things I usually love doing don’t excite me anymore. My work has become a trance, my hobbies somewhat burdensome, and even my favourite music seems like it’s just noise. I’m still as productive as I ever was, and to all but my closest friends it looks like I’m the same as I was before. But I just cannot be passionate about anything anymore. How do I get past this?