My grandfather taught to avoid speaking negatively about others, but encouraged unreservedly sharing positive experiences when asked. He would not associate with a toxic individual even if it might have led to personal gain; refused to abandon friends by concealing his relationships with them; and refused to withhold good opinion of trusted colleagues when asked pointedly.
Accept demands that you abandon friends or conceal your good opinions for fear of their retribution and you import their scarcity into your heart. Should you be so commanded by someone, avoid the entanglement of drama altogether. Take great care with those who offer you financial, physical or emotional rewards for turning your back on your own good conscience, in exchange for your silence. Stay true to yourself and what you truly believe in.