Please remember! This translation is my personal work It is sometimes difficult to translate word for word from Spanish to English, so it may sound awkward in one languange when it is perfectly natural in the other But I think you can get the general idea!

You want to tell her that you love her more than anything
And as a friend, what advice can I give you
Tell her that you can't live without her
(You feel) what you never felt for me
And in your eyes, I can see that tenderness
The longing, and the love, and the craziness
And in my mind, I can only see
you sweetly kissing her skin
And it kills me to have to admit
that you look good with her

If you love her, go tell her "I love you"
You shouldn't lose another minute without her
She's waiting for you, and I'll stay here
If you love her, go tell her "I love you"
You deserve to have her in your arms forever, with you forever
And me, I'll stay here