Soulmate (noun)

1. A person with whom one has a strong affinity, shared values and tastes, and often a romantic bond.
2. A person with whom one has a strong affinity and shared values and tastes, often romantic bond.

Origin:

From soul + mate.

Examples:

1. He knew she was his soulmate the moment he met her.
2. She was convinced that he was her soulmate.
3. They were each other's soulmates, completing each other in every way.
4. He always believed that there was one special person, his soulmate, meant for him.
5. She felt a deep connection with him, it was like they were soulmates.