Is there a last chance?

Presuming that every person has a sole mate what if you screw up with your sole mate?..Will you become a lost sole?...lonely forever?..What happens?.... A second train will come...that is why I ask myself for some long time..what if she was the one,I screwed and she is with another guy. I mean on a selfish line,did she found another sole mate?Why she gets over that fast and I have to wait so long?It is not like I am the only one to blame ??!?!..how these things works. It's not like I try to solve these problems but I am having some close to reality dreams that put me on thinking .. What will happen....