If things are tough, remember that every flower had to go through a whole lot of dirt to get there. So do not grieve about a bitter experience. The present is slipping by while you are regretting the past and worrying about the future. Regret will not prevent tomorrow's sorrows; it will only rob today of its strength.
There's a different set of writers and a different director for the films, but Marvel has turned it into a pretty spectacular job.