A loving friend is one who cares about you enough to say what is true. This truth may be about dangers you face and even character issues that you need to examine. But failing to be truthful may also have an aggressive, nasty, secretive component of which to be aware. God has provided a way for you to be able to recognize enemies disguised as friends. Proverbs provides the insight you need to protect yourself and your children.
Proverbs 27:5-6 combines two real life examples to help you discern between friends and those who would hurt you.
Better is open rebuke than hidden love. Faithful are the wounds of a friend; profuse are the kisses of an enemy.
In verse 5, the first example teaches genuine friendship is about honesty and truthfulness. A true friend will be open even to the point speaking honestly when you wander off course. This requires courage but it is the mark of a friend you can trust. However, if one hides what is true, or conceals it to gain some advantage over you, friendship is not his goal. One commentary suggests the motives behind this hidden love are cowardly and even timid at its core. In contrast, open, loving rebuke is potent; hidden love is impotent. Wise words, indeed.
The example in verse 6 is even more explicit and practical. Following the lead of verse 5, faithfulness in friendships is demonstrated by speaking the truth even when it hurts, i.e. the wounds of a friend. This is a good thing. A friendship that lacks loving, honest rebuke is no friendship at all.