Wow.....I've not heard the song but I'll have to look it up. I always thought that even on Demon Blood that Sam was in control. He seemed to be more confident in his abilities and of course it gave him more strength (like steroids) I also thought that it took him a while to fully go in to withdrawals. He'd been out of db for weeks when he was hurting so bad before he met up with Ruby just before they went off and killed Lillith.
I always saw him as a man on a mission. Demon Blood allowed him to do what needed to be done. kill the demon or send it back to hell and save the human host or save someone. I never figured him to just want it for the "high" or the "buzz". Of course I'm sure it did just that...gave some kind of buzz. "When the Levee Breaks" is one of the best episodes ever and I love how in the end of Season 5 when Dean was losing his faith and was so lost that Sam was the one to stay steadfast and true. While everyone around him was floundering. Even Bobby and Cas.