A Shakespearean Sonnet on Valentine's Day

My love is strengthen'd though more weak in seeming;
I love not less, though less the show appear:
That love is merchandiz'd whose rich esteeming
The owner's tongue doth publish every where.
Our love was new, and then but in the Spring,
When I was wont to greet it with my lays;
As Philomel in summer's front doth sing.
And stops her pipe in growth of riper days:
Not that the summer is less pleasant now
Than when her mournful hymns did hush the night,
But that wild music burdens every bough,
And sweets grown common lose their dear delight,
Therefore, like her, I sometime hold my tongue,
Because I would not dull you with my song.