Hello Elwood

It is a nice romantic song with apt refrains and stanzas voicing deep love. I appreciate the fact that you have such undying love for your wife, which comes out pretty clearly in the verses. The way she supported you and the children, through the years to the present is shown briefly but in effective lines.
Your similes and metaphors make a special impact on the reader.
"My constant star
You're my blessed rock"
These figures explain the kind of person your wife is and how much you need her. There can't be a better tribute to one's life partner than this.

Imagery-
This is the very spine of the song. It is visual and aural as well. I see the sweet person and hear to sound of love she inspires in you.
"I knew right away
You're all I need"

Your explanation regarding the success of this song shows that one can do go to any length to prove the bonding love between the two lovers joined forever.

It flows well.

Write on!