Most Helpful Guy
People aren't always gonna return the treatment. That sucks, but it's true. Even if you're the nicest person ever, there's gonna be people who treat you like shit.
But that doesn't make it justified to treat other people like shit, either.
How you treat other people, in terms or respect and kindness, is not dependant on how they treat you.
How you treat them and how they treat you are two different things. Neither should effect the other like that. Sorry, but it's still on you how you treat them. It's still on them how they treat you. It sucks being nice sometimes, but it's still the right thing to do. It's hard sometimes.
Most Helpful Girl
Treat others like you'd want to be treated.
That said, it's alright to offend people at times as it is alright to get offended at times. You don't need to be liked by everyone.
Instead of feeling you need to be worthy of hanging around with them, think about if they are worthy enough to hang around with you? And you're right you shouldn't just trust anyone, trust is earned! But you do need to offer them a way to earn it.