I trust people to be who and what they are. Try trusting people by their actions and that includes what comes out of their mouths. However, if the words are sweet but the actions are not -- the actions are the true person.

A really important thing to know is how to trust yourself and that might mean improving your judgment skills. It always pains me when I see people say "So-and-so really hurts me/lies to me/beats me/steals all my money/abuses the kids/abuses me but not the kids/cheats on me/other seriously bad things but I love so-and-so. The way I see that--you can trust So-and-so to be an abuse/liar/thief/commiter other seriously bad acts but none of that is a good reason to love So-and-so and I guarantee you can trust So-and-so to continue to do those things as long as you put up with them.

Rational people do not just "turn on" their friends and families without provocation. It is true people can leave. But any relationship where the person just willfully leaves in the middle of the night without saying goodbye and why (I'm not talking about sudden death here) wasn't a healthy relationship to begin with.

Learn to trust yourself. I really do think that being reasonably self-sufficient and confident attracts other people of like mind and makes short term nuisances of scam artists and emotional victims who are always trolling for victims <-- but you shouldn't want them around anyway. I hope this helps.