But that is of course a question of believe

I personally believe that we manipulate the universe all the time. Even if we would kill our self we would manipulate the universe. And we ,"human", is a part of the universe. All our choses are consiqenses of the other choses of universe as a whole.
I don't see why it would come back threefold. The only way that could happen in my believe is if someone actually took action and trow a curse on you.
BUT! A love spell may actually be a curse. Be carefull so that you dont curse yourself I would say.
PS, I know this thread is "dead" but I wantet to point that out:$