A natural term for that kind of relationship is “mutually respectful relationship.” You could also describe it as a “trusting and courteous relationship” or a “harmonious, respectful bond.”

Best single-word and short phrases

  • Mutually respectful relationship
  • Trusting relationship
  • Courteous relationship
  • Harmonious relationship
  • Considerate relationship
  • Supportive relationship

Each of these highlights slightly different aspects, but “mutually respectful” and “harmonious” together most strongly capture trust, consideration, and politeness in a positive atmosphere.

Slightly more descriptive options

If you want something a bit richer (for writing, profiles, or forums), you might say:

  • “A warm, trusting, and respectful relationship.”
  • “A considerate and harmonious dynamic between two people.”
  • “A relationship built on mutual trust, courtesy, and respect.”

These make it clear that both people are actively contributing to that positive, polite atmosphere.

Mini example (to test the wording)

“Over the years, we’ve built a mutually respectful relationship where we trust each other’s judgment, stay considerate of each other’s feelings, and keep our conversations polite and constructive.”

If you tell me where you plan to use the term (novel, academic essay, dating profile, etc.), I can tailor a version that fits that context perfectly.