>>1 You're questions seem related to each other so I'm not going to split this up into three answers. To trust someone is to have a strong enough bond with someone that you know they will never intentionally lie or withhold things from you. I guess a better way of describing trust is that it's more about the probability that they will lie to you. People mainly tell the truth and how likely it is that they will depends on the person. Under the right circumstances though anyone will lie. So if you're looking at complete trust then it's something that goes beyond the probabilities and circumstances where you can truly trust them with anything. It's something really special though so I always end up describing things like that as a true bond or connection. I don't know if they exist though, because after all, we're all still imperfect humans.
I know I started with your second question but they all go together so just bare with me. It is both your second and third questions that answer your first one. You want to detach yourself from the world and you ask if you can trust people. It's only after giving up on the world that you can ask these kind of questions and what's next is the contradictory situation we are left with. The answer is that we are born into this world and are stuck in it. We want to exist in a different world but we truly know deep down that there's no leaving this one. So we have two perceptions on this world; 1) We've given up and will truly find nothing meaningful and fulfilling in this life but then after that we get, 2) We know that we're stuck here so we wonder if there truly is something here for us. That is a contradictory perception. To believe two things that contradict each other.
I don't know how well I explained that but the fact is that this life is contradictory. It's designed in a way where we both want and feel two opposite things. An example would be when it comes to people. If you think everyone else is just shallow and boring then you want two things; you don't want to see other people because they annoy you but you also want to see other people in hopes that you find someone interesting.
I don't think we can truly disconnect from this world. I think that would just be living in denial and hiding from the truth. It reminds me of a question actually; Would you rather live a happy lie or see a harsh truth? I think I said it wrong but you get the idea. It's hard to say which path is the right one to take sometimes.
Anyway, I don't know how helpful any of this is going to be but I'll leave you with one last thought.
If you don't like the real world then why not create your own world? You can take that anyway you want ^^
PS I think I might have gotten the wrong idea from the first one so my bad... And I guess this probably wasn't the kind of answers you were looking for. Oh well, I'll post it anyway just in case.