I love how the different sections blend together, and the overall feeling of despair. Melodically I think it's pretty solid, and I especially like that bit at around 1:50, when the lead guitar drops into that dissonant tone and just hangs there as the song progresses. Plenty of variation and movement within 5 minutes to keep the listener engaged while maintaining a consistent feel. Great work.
One little thing, because it could just be my sound system, the kick drum seems like it could use some work. I'm not sure if it's over compressed, or just too hot in the mix, or what. Either way it didn't really ruin the song, just sort of stuck out to me, and I wanted to have some sort of constructive feedback for you so there it is lol.