John Dowland's stuff is incredible.. but he's not really classical
It's almost like Elizabethan sonnets put to music. I hope it's not too far off of what you would be interested in but I thought I would share.
The lyrics, I feel, are about a man who finally finds a woman that he sees as constant; doesn't change her mind, says one thing and does it, etc. (I don't feel this about women but I guess that's the stereotype). BUT she isn't interested in him and is obviously upset but knows that "love is free" and he can't change her.