"The first day I saw your handsome face,
The first day you ever left a single trace,
Of love and affection between you and I,
I knew that day we would never say good-bye,"

-I think, personally, the problem with writing a long sentence and trying to make it rhyme at the same time, is that you tend to forget what you were trying to rhyme it with in the first place by the time you finish that sentence. Or, if you add too many syllables to one sentence, it sometimes sound like two when you read it out loud...so it kind of throws you off the rhyme scheme.

"The first day I heard your sweet voice,
That first day we made the choice,
To be together now, and forever,
Knowing this was something nothing could sever,"

-Again, it's the long sentence that throws you off. There was a similar beat in the first three sentences, but the fourth one had an extra something to it.

"The first day I felt your strong embrace
That wonderful day nothing could replace,
You stole my heart, promised to never make me cry,
You won me over, without a single thought of another guy,"

-Sometimes it's okay not to be descriptive in your writing, I think so anyway. I noticed you tend to put adjectives in places where one word less could have improve the sentence. Ugh, I don't think I'm making sense, but for example...

"The first day I felt your embrace
That day nothing could replace,
You stole my heart, promised to never make me cry,
You won me over, I thought of no another guy,"

I dunno. Don't change your poem over that example, it was just a quick one.

"From that first, first day,
To the million and beyond I will say,
I love you and mean it more than you will ever know,
Just know that you are in my heart wherever it is I go. "

-Again, taking out a few words here or there might improve the rhythm of your poem.

Very sweet poem and you're right, slant rhymes are okay. =)

Oh, one more thing...try reading your poems out loud when you're revising or writing a poem the next time. I find that helps a lot.

A beautifuly written, and heart-warming poem. You painted a wonderful picture, and I could see it all so clearly!

mandy :)