sparkmate

Term comes from the Transformers franchise.

It basically means your significant other, your other half, or the one for you. It is different from a soulmate, as soulmates are close friends or family who are an important part of your life, while a sparkmate is the only one who completes you, who is your true love.
Some people however, don’t have a sparkmate, such as aromantic people, and some people can even have multiple, such as polyamorous people.
Your sparkmate is the most important person in your life, and you will always be together.