Overall, I thought this was good. There were several minor flow errors, but you'll hear them if you try to read this aloud. Most of the time it's a line that's one syllable too short, or something else small like that. No terrible offenses.
My nitpicking nature is demanding that I tell you that I think in stanza 10, that hand/end rhyme is a bit too much of a stretch.
I'd also like to see the end rhyme. Sometimes changing the last line like that works, but I think because this is so long, the reader gets used to the rhyming scheme, and the end is just like hitting a brick wall, instead of coming to that gentle stop, like that tide pushing you back to shore ;)