Yes! Except I would phrase it differently: Never loan money to a friend or family member - either give money or don't. Oftentimes, the person you gave money to will later give you as much or more than you gave them, but that isn't a loan repayment, it's just them being kind to you in the same way you were kind to them.

To hnriot, who I can't respond to: No, it's not being a chump to willingly give money to those you are close to. The other side of the "be willing to give money to friends" coin is "be aware and careful of who you consider friends". You may be a chump if you give money to people actively taking advantage of your willingness to do so, but those people aren't friends. You should never give money to people who aren't your friends, and you probably shouldn't loan it to them either, unless you're in the lending business.