Will knowing my type help me know the type of person with whom I would be most happy?

No, but...

Relationships are too complex, and what makes people happy is too diverse, for one instrument to capture such information reliably.

Successful and happy couples have included people who share the exact same personality type, people whose types are opposite, and people with some preferences in common and others distinct.

That said, the MBTI tool is often used in couples counseling because it can help reveal normal healthy differences between partners.

A couple who takes the MBTI assessment and then learns to respect and value each person’s style has built at least part of the foundation for a happy relationship.