A Lesson About Resilience

The dictionary says resilience means:

• the power or ability to return to the original form, position, etc., after being bent, compressed, or stretched; elasticity.
• ability to recover readily from illness, depression, adversity, or the like; buoyancy.

I’m an outdoorsy guy, I fancy myself strong and rugged and brave. I look to Theodore Roosevelt and Ernest Hemingway for inspiration on how to manage things like challenge, adversity, adventure. My point is really that to me, resilience has always been about toughness; about getting knocked down, and getting back up; about finding not just the lesson, but also the joy in struggle.
I jokingly say that resilience is my superpower. If I’m backpacking, my resilience allows me to go that last mile, when everything hurts and I’m really tired and hungry. If I’m hiking in the thin-air of the Colorado mountains, resilience spurs me to just take the next step, and the next step, and the next step - until I get to the top.
I was talking with coaching a peer recently, and the topic of resilience came up. I shared my take on it, and she pushed back a little. She agreed, resilience is largely about toughness, but she felt I missed an important part of the formula. She mentioned vulnerability. She feels strongly that resilience also includes a component of vulnerability. She made a compelling case, and while I did not disagree, I struggled to see the connection in a way that made sense to me.
Vulnerability implies: susceptibility to risk, exposure to potential hazard. When I look from my own perspective vulnerability implies weakness. Now before anyone jumps on me for saying that - let me clarify; I am not saying vulnerability is bad. I am saying that from my perspective, I associate with risk and exposure; it’s something to be managed. And, there are often times making ourselves vulnerable is wholly appropriate.  As I said, I didn’t disagree with her her, I simply struggled to see the connection first hand.
Yesterday, I was at the gym, an older gentleman a few machines down finished his workout and was wiping down the treadmill. As he sprayed it with cleaner, he overshot giving the two women in front of him a healthy spritz. They startled and screeched a little.  He immediately smiled, apologized, and then added “there’s no charge for that!”. They laughed, he laughed, even I laughed.
In that moment, I understood what my friend meant. If I had sprayed cleaner on someone at the gym and startled them, I would have certainly apologized, likely in a sheepish manner. I would have thought to myself, “ok, you messed that up - let’s try to not do that again”, I would have moved on. But that isn’t what he did, is it? I mean it is, but he took it a step further - he made himself vulnerable to others. For him, that was part of his “getting back up”; part of his “ability to return to original form”.  
What do you think? How do you see resilience?