Oh dear, yet another misquote or non-truth from Scott th Ratbag.
Maybe you should try learning these first two verses by heart or by rote.
When you get these two down pat I'll post the other four for you to peruse at you leisure.

There Is a Lady Sweet and Kind

Thomas Ford

There is a lady sweet and kind,
Was never face so pleas'd my mind;
I did but see her passing by,
And yet I love her till I die.

Her gesture, motion, and her smiles,
Her wit, her voice, my heart beguiles,
Beguiles my heart, I know not why,
And yet I love her till I die

I'm unfazed by your replacing "did but" with your "only" version however your swapping of "And yet I" with "Yet I'll" while keeping the three-syllables needed, for the iambic pentameter length, it is an appalling phrase for poetry albeit 500 years later.

If you must change Ford's
And yet I love her till I die, ... why not use
Yet I will love her till I die, ... or better still pinch one of the three existing end lines which Ford has used for his last three verses, which were:
For I will love her till I die.
and the later verse's questioning end-lines
Yet would I love her till I die.
Yet will I love her till I die.