Mary - I have a nice version of "I'll Be All Smiles Tonight" by the Louvin Brothers. I'm sure there are more recordings by Country artists - I haven't heard many Bluegrass singers perform the tune. Here are the lyrics:

I'll Be All Smiles Tonight

I'll deck my brow with roses the loved ones may be there
And gems that others gave me will shine within my hair
And even those who know me will think my heart is light
Though my heart may break tomorrow, I'll be all smiles tonight

Chorus:
    I'll be all smiles tonight, Love, I'll be all smiles tonight
    Though my heart may break tomorrow, I'll be all smiles tonight

Oh when the dance commences, Oh how I will rejoice
I'll sing the songs he taught me without a faltering voice
When the flattering ones come around me they'll think my heart is light
Though my heart may break tomorrow, I'll be all smiles tonight

Chorus

And when the room he entered with a bride upon his arm
I stood and gazed upon him as though he was a charm
And then he smiled upon her as once he'd smiled on me
They knew not what I suffered, they found no change in me

Chorus

And when the dance is over and all have gone to rest
I'll think of him, dear Mother, the one that I love best
He once did love me dearly and ne'er from me would part
He sought not to deceive me, false friends have changed his heart

Chorus