Relationships generally consist of exactly what one brings to them. If they think they found a soul mate and it makes for a better relationship, what is the harm?

I know a couple of couples who swear that they are and always were soul mates. They’ve been happy together for decades. Who is to say that they are wrong?

Even Schopenhauer, iirc aserted that reality is largely will and representation. I don't know if he had a soul mate.