Does Romeo and Juliet have no control over their lives and is instead subject to the wider forces of fate and destiny?

They have great control over their lives.  They are
constantly making decisions, often rash ones, that lead to their untimely deaths.  Their
inability to be patient and love moderately as Friar Lawrence warned Romeo, was
responsible for their deaths.  Their unwillingness to be straightforward with their love
and instead put people like Friar Lawrence in difficult situations played a large part
in their death.  Finally, of course, their impulsive behavior and fascination with death
sealed their fate.  Whenever the possibility of living without the other arose, their
first thought was always suicide.  Even when they were talked down from such drastic
measures, it always remained firmly in their heads.  That's why it's not so surprising
that they each chose to take their own lives at the end.  Notice the key word being
"chose" meaning they had a decision and fate had little to nothing to do with it.  Sure,
they ran into some bad luck and challenges of being together, but I haven't met a
married couple who hasn't faced these difficulties to some
extent.