“If you hang out with crazy people, the insane starts to sound normal”
What that means is if you hang out with people that do drugs, or binge drink or hold up doughnut shops, then doing drugs, drinking heavily and armed robbery become normalized pretty quickly.
If you hang out with people that run marathons, complete Ironmans and volunteer at the local food bank, then being active, dedicated and compassionate become your normal too.
You become who you associate with. Hang with the right crowd