I dislike the term soulmate as it generally is associated with the idea that there is one other person in this world that is the perfect mate. Out of roughly 6.6 billion people over 148,940,000 sq km of land the odds of running into the one person that you are meant to be with is something that only the likes of PF could tell you. I can say in highly un-scientific terms that it's quite unlikely to happen.

Now, to answer your question, yes. I think a lot of relationships can last a long time if both persons are honest, especially at the onset, and they both work hard at keeping it strong.

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Put me on wheels and I'll turn tricks.

Clever? Nah, I ran out of that years ago. But if you find this, let me know, k?
"The road goes ever on..." ~ Tolkien

In memory of my friend skip...
Go then, there are other worlds than these