You're just an empath.
His arms wrapped around your body in a comforting embrace, although in fact everything should have been the other way around. Now, being in his arms, you were crying. And why? Simply because you put yourself in his place and your empathy made itself known...
Thoughts about how he might feel when he transforms into a werewolf, when he gets these stupid wounds and abrasions... Or thoughts about how he might consider himself a beast among normal people didn't give you any peace.
Remus whispered soothing words into your ear, though the words weren't as soothing as his voice. Gently rocking back and forth like a mother would rock her child, he stroked your head. He found your empathy endearing.
"Shhh, shhh...It's okay...Don't cry."