"From the very start"
5 syllables not 4

"Of our relationship"
6 not 5

"Our promise we'll keep forever"
8 not 9

This is okay. Your language is basic, with the basic message that we'll be together forever blahblah, you just added trust and form to make it more interesting, but it still needs some improvment. METAPHORS! Are great things, wonderful things, in fact. Perhaps to extend yourself a little further use some of those? It'll make the poem more interesting and it really brings out the authors tallent.
Still, I respect that you've chosen this form, it is hard to write, I know. Good luck with the corrections to the line lengths because I have no idea how they could be changed, hah.

4/5

jess ~

OOPPPs
Forgot to make suggestions for these.
4th line "Right from the start"
fifth "relationship" to "relations"

Beautifuly written poem. The wording was great and allowed the emotions to come through. It was easy to understand. I can truly relate to it. I saw nothing wrong with it. I gave it a 5/5.

Oh and I like the image that this poem gave. Keep up the great work =)

"Of our relationship" - 6 syllables.
Seeing as of = 1, our = 1, and relationship = 4.
There should only be 5 in this stanza.

"Our promise we'll keep forever" = 8
our = 1, promise =2, we'll = 1, keep = 1, forever =3
1+2+1+1+3=8
just change 'we'll' to we will. :]

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Flow was a bit off, darling. I think that was due to the two lines with wrong syllable count. once you correct that, you should have a great poem. I really enjoyed the read. :]]