Trust is whether or not you can keep your mouth shut and believe that another person will properly operationalize your definition of "careful" while handling something precious to you like a fragile memento, sentimental antique, comic book, child or heart. The keeping your mouth shut is the hard part - you have to trust them enough to allow them to earn your trust - it must be filled as it gets used up; it's a perpetual emotion machine.
I promise not to do that again.
I love a lot of people I don't trust. Their presence in the world makes me happy, I'm glad they're around, but I wouldn't give them my important shit, and I damn sure wouldn't hand them my heart and feelings. Sometimes you come by that knowledge/realization the hard way, and sometimes you just know. Often, experience allows you to pick them out before you get your heart broken, and people mistake this toughness for wisdom. It might be both - I'm not smart enough to tell the difference.
I find that exposure (in terms of time) makes no difference here, some people will simply have your back, and others will not. Some of the people I feel this way about I have known for decades and spent lots of time with, others I hardly ever see.
I trust people I don't love; there is a kind of intense value that I place in a person who is loyal and honest and dependable which is like love without quite being love; a really intense form of like, a kind of love that Greek people probably have a word for and German people have a word to make fun of. The most interesting people in this category are folks who do or have done deplorable things but who are really decent to me personally - I like to think that this is indicative of an overall effort to be better, and I have to value that or I'd be a hypocritical bastard. Moreso. Again. Whatever.
That is all. I now return you to your Thursday, which I have decided to call Jerry. So enjoy Jerry.