how do you know?

how do you know someone is the right one?
there's been so many times I thought I had the right one,
turned out to be false,
Thought I was "in-love", but apparently I was not,
Is there an "in-love" or is it all just a hoax?
Do we, just love whoever comes into our lives, for however long they are supposed to be in our lives,
if they end up staying til' death do us part, than great, but if not and we move on,
to the next,
I am sure that there is "in-love",
I am sure there is "the one" for all,
I am sure I am just be cynical....