It took the first draft of this idea being complete before I noticed it was similar to Taleb's notion of Anti-fragility. The comparison is obvious enough but worth understanding from a more human angle (as opposed to the systems angle preferred in NNT's book).
Nobody can avoid getting hurt or betrayed in life. And nobody's indestructible. You ought to care enough that terrible things devastate you. Obviously, it's disruptive to be devastated, so, ya know, not too often, not that it even needs to be said.
The real question is what happens next: Do you become cynical? Are you slower to trust? Do you find yourself seeing the flaws of a few in the minds of many? Or do you dedicate yourself to being better than the examples that disappointed you? Do you use every negative to build a better way to be in their shoes?
I once heard that to be an excellent landlord, you have to be a tenant. And to be an excellent tenant, you ought to be a landlord. They say, in the rare cases a fresh-out-of-college success hungry startup founder needs to hear it, that to be a good boss you need to be an employee first.
I think it's because our empathy isn't infinite, and we need practice to understand where people are coming from. Sometimes that practice is in a role, but sometimes it isn't. Sometimes it's just being burnt by bad actors.
What we really ought to do is strive to be people who grow from hurt, and open ourselves up to the vulnerability that will make use stronger as quickly as possible. I don't think this is easy, nor something traditional wisdom can help with all that much – I recall hearing stories of people whose spouses died and their whole lives essentially ended decades before their bodies failed. That dedication to someone you love is admirable, but the devastation was far too permanent. Life is too precious to sit in sadness forever.
The real trick is trying to figure out when you know you can recover and become stronger from disappointment and tragedy. And that's something I don't have much advice on.