Sometimes a person comes along and makes you feel so strongly that this is it, that it's not just love at that moment, the feeling is strong enough to make a complete non-believer believe in destiny and supernatural forces.
But if the other person doesn't feel the same way or at least a little bit, what a shock!
"It's just not possible for her to not love me or even act like she doesn't care without extreme effort. It's not possible for her to live a lie for the rest of her life. She knows as well as I do that she has met her soulmate. Then what is this all about?!!!"
Such a shock will take a long time to truly recover from, if ever. Life is completely changed.