"Ma plus grande douleur dans la vie est que je ne pourrai jamais me voir performer en direct."

Simplified Meaning:

The speaker feels very sad because they will never get to watch themselves doing what they love, just like their fans do. Imagine you are a musician who plays a great concert. You can see the people enjoying it, but you can never experience what it's like to be in the audience, enjoying your own music. For example, think about a chef who makes the most delicious meals. They can taste the food, but it's never the same as being a guest at a fancy restaurant and being surprised by an amazing dish. This feeling is a mix of curiosity and frustration because you can't enjoy your own talent from an outside perspective. If you apply this idea, it might remind you to value feedback from others since they see things you can't see about yourself. It can also encourage you to appreciate the unique viewpoint each person has, including your own, which you bring to the world through your actions.