There's some truth to it, but things don't always have to turn out this way. There isn't a fixed linear progression to be followed. There isn't just one ending. It fails to take into account the human will to hang on to things they believe in, the spirit to fight for the things they want, the capacity to love, forgive and hope. But then again, it takes two to make a thing go right. I guess half the battle's lost when only one is fighting for a cause he/she believes in.
There are no reset buttons in life, but there are windows of opportunity to make amendments. They may not present themselves for long, but when they do, no one should hesitate and say let's wait for the other to make the first move. That may well be the last chance at working things out. That may well be the defining moment that sets the gears in motion for a transition to the next stage. Some things come with experience. One would be a fool to not learn from them.