it's disappointment, loneliness, the sad one, when you do something, and suddenly you realize that nobody really cares, and you could as well not do it at all, and nobody would notice, you could as well not set your foot outside, ever, and notbody would mind, miss you. the passive anger in the background, "it's not fair! how is it that basically anybody else WOULD be missed, that anyone's else actions matter, and their inaction would be noticed? I want that privilege too! How is it that people consider it to be such a common thing? It's not!".
the anger fades into unease, your throat tightens (i mean that feeling, can't remember how it's called properly), and you feel like you're going/you want to cry, but you can't, it just doesn't come, and you just stare mindleslly. slowly, all the feelings and thoughts fade away, and you're left an empty, cold, dark shell.
...i have seen the movie, but I'm pretty sure the song would make me feel the same even if I haven't.
btw, watch the movie, it's pretty good, IMO.
about the part of giving recommendations... I don't really dare to say what is an "emotionally complex" piece, I think my perception of something like this is mostly different from most people, and I'm not willing to expose it for possibly being challenged. BUT, Massive Attack should generally fall into this cathegory, almost anything by them.
...BUT... reminded by the Mad World posted here by someone, there's one song that makes chills go down my spine, and I'd gladly and immediately tear apart anyone who said it was not emotionally strong and complex (yes, more so if you've seen the movie, but only because it compiles all the feelings from the movie itself, and to me, it's strong, confusing, manifold: beautiful, scary, sad, noble, cathartic yet solving/ending nothing really, dramatic while completely peaceful, it makes me want to cry and smile at the same time, makes me thing "i understand" while thinking "what the fuck was that?" at the same time... first time I heard it, i REALLY cried, because it HURT immensely, the song physically hurt, and I said about it the same I said about the movie: "It's horrible, cruel, sad and it hurts. I hate it. It's one of the best songs I've ever heard and it's always going to be one of my all-time favorites.")
Enjoy:
http://www.youtube.com/watch?v=nNx-1M9MqM4
(P.S. how the hell do you embed videos directly into the post? i can't remember or find instructions anywhere)