A trusty friend is someone who is dependable and reliable. Synonyms for trusty friend include faithful companion, loyal sidekick, steadfast ally, devoted confidant, dependable mate, unwavering supporter, and reliable buddy. A steadfast ally is one who stands by your side regardless of the circumstances. A devoted confidant is someone who you can share your innermost thoughts and secrets with. A dependable mate is a reliable friend who can be counted on to be there when you need them. A loyal sidekick is a trustworthy companion who sticks with you through thick and thin. These synonyms all convey the idea of a close and reliable friend who you can count on to be there for you.