The pre-raphaelite poet Elizabeth Barratt Browning, one of my favourites:
If thou must love me, let it be for nought
If thou must love me, let it be for nought
Except for love's sake only. Do not say
"I love her for her smile her look her way
Of speaking gently, for a trick of thought
That falls in well with mine, and certes brought
A sense of ease on such a day"
For these things in themselves, Beloved, may
Be changed, or change for thee, and love, so wrought,
May be unwrought so. Neither love me for
Thine own dear pity's wiping my cheek dry,
A creature might forget to weep, who bore
Thy comfort long, and lose thy love thereby!
But love me for love's sake, that evermore
Thou may'st love on, through love's eternity.
Thomas Hardy wrote some very beautiful although hauntingly sad poetry as well as his novels.
I found this book has a super selection for more exploration - Nation's Favourite Love Poems:
http://www.amazon.co.uk/Nations-Favourite-Love-Poems-Poetry/dp/056338378X
Lxx