How do I handle being the person who always says no?

You have trained yourself to see the risks others miss, and the reward is that you often have to be the one who says no. It can feel like you are standing against everyone's plans, the wall between people and what they want. That is a lonely place to sit. But your no is not the enemy of their goals. It is the guardrail that keeps their goals from ending in disaster. The people who resist you in the moment are usually the ones your no protects. They just cannot see it yet. You are not against them. You are for the version of them that does not get burned. Try to say no in a way that shows the why, not just the wall. When you can, offer the path that does work alongside the one that does not. It softens the role without weakening the line, and it reminds you, and them, that you are on the same side.