Two related, and really useful, ideas from two psychologists:

You don’t need to feel better—prepared, ready, in control—before you do the difficult thing. All life asks of you is that you participate. When you avoid negative emotions, you make them feel stronger. Steven C. Hayes explores experiential avoidance and acceptance and commitment therapy (ACT) in this post.

You can get better at dealing with difficult emotions by practicing emotional endurance. Rather than regulating or coping with the emotion, be present with it—tolerate it, and be willing to embrace it. Nick Wignall explores emotional endurance in this post. Nick also wrote about how emotional endurance can build up confidence.