Having someone you can trust is quite rare nowadays. When the negatives outweigh the benefits, can you confidently say your friends will have your back? It is not also about trust. A person can mean well but fail to act when it really matters. Usually the people who have your back will have good morals and honor, something that’s quite missing in the criminal world.
In regards to traits, people who are trustworthy are often reliable, have their own stuff together, more courageous than normal, have a strong will, and have initiative. The combination of these traits eliminates many people from the population, which is why it’s so hard to form genuine friendships these days.