Avoid people who only treat you well if you're well off—keep a tight circle of people who will stick around even while the ship is sinking.
Quality people are rare in this world so don’t expect to find many. The more successful you are, the more people will magically appear to help you enjoy that success. Look at these people for what they are and don’t make the mistake of misinterpreting their presence as meaningful. The people you can trust are the one’s who stick with you through it all and don’t question your character in the process. The others can and should be gleefully discarded.