To be honest, I find sharing negative emotions is also a sign of trust and vulnerability. One of the most intimate experiences for me was when my partner felt safe to cry in front of me, and I held him, and I felt incredibly trusted being able to see this side of him. It deepened our bond massively.
It's not that I want to see my loved one in pain, but rather I am glad that I am someone he feels safe to come to honestly when he IS in pain, as all people are at times.