When in your life have you had a "now or never" moment?

The last time I was on a high diving board. I suddenly got scared and couldn't do the dive....tried just jumping and froze. That was the moment. Now or never. And I chose never.

Buying my house, getting back on a plane after years of not flying, and going on a blind date after my divorce

An important timed injection and I had to stab myself or regret it.