If you’ve been lied to, taken advantage of, tricked, or betrayed, that really sucks but it’s also partially your fault. I know it’s a difficult thing to hear, but misplacing your trust is something you need to acknowledge and work on if you constantly find yourself being hurt by others in those ways.
More often than not, we trust others simply due to proximity, a smile, how they look, how they are dressed, how many mutual friends you have, etc. This is especially problematic when they claim to be of the same religion or cultural practice as you. Because others claim to have similar hobbies or beliefs, we subconsciously project our own identity onto them and it opens up a flood of opportunities for complete strangers to take advantage of your trust.
What we need to do is be more discerning and wise with who we choose to trust and confide in. Even in the world of business, we should exercise caution (I’ve heard many tales of people claiming to be Christian just to get a discount on services) because people are always looking for a deal that’s best for them and what’s best for them isn’t always at all good for you.
I’m not saying to not trust anyone ever, but rather to just use good judgement and not to make assumptions about the quality of someone’s character just from their words.