I think it was Jim Rohn who was best known for saying 'you're the sum total of the 5 people you spend the most time with' So true!
Having a positive, supportive peer group is massively important. No matter how smart and well-intentioned you are, it can be difficult to make it on your own. A good peer group keeps you awake and gives you a point of reference for your own actions (or lack of them!).
You nailed it there @septimusmaximus! and that 'sum total of the 5 closest people' quote is so true, especially if you just take a look around online or in the real world, so so true!