I never said he couldn’t express his pain. I said, regardless of genders, this way of expressing it is simply rude and not a good way to communicate in any kind of relationship. When someone brings up something that is bothering them, and your immediate response is “yeah, but me”, you’re being a jerk. Since this seems to be escaping you, this doesn’t mean the other person isn’t allowed to talk about their feelings. They simply need to be an adult and do it at a more appropriate time or in a more appropriate way. Conversations like this aren’t a battle to be won, they are a tool used to solve a problem or simply vent frustration.

You seem to be looking at this in a very black and white way. Therapy can help with that. It’s not a fun way to go through life.