It took many years and many trials and tribulations before I learned to accept that everything truly does happen for a reason. There have been many times that I have dealt with what I was certain were horrible situations only to discover that there had been a plan after all. The world works as the world wills and everything will work out for the best from the end of relationships to the loss of some dreams.
People can look sideways at this and shake their heads, but the fact remains. You need to have faith and let go. Have faith that the situation you find untenable, the loss of a job or the end of a relationship, is for the best. Wipe down your face and stop fighting the inevitable. Crying won't fix the job; yelling won't fix the relationship. Accept that in those situations, you are powerless. And accept that there is a plan, you just can't see it yet.
When the door closes, the window opens. If the relationship ends, it wasn't meant to be. There will be other relationships, and one of them WILL last. If the job is lost, it simply means that a better job, a better fit and one that will make you happier, is out there. And everyone, good or bad, has given you something to make you a better person, but it's up to you to find out what it is. But that first step is acceptance. Accept that it's OK that things did not work out the way you wanted, and really mean it.
Most of us spend a good portion of our lives railing against the inevitable instead of accepting the plan we cannot see. We can't accept it for a number of reasons: it doesn't fit with our plan, we were content with the situation as it stood, or even we are too set with that path that change is nearly impossible. But, by relinquishing control to the flow of the planet, we will find our path.
That is not to say that the right things don't require work. I recognize that had any of my relationships followed a different path, I would likely not have ended up with Big Guy. However, all relationships require work, even good ones. Big Guy and I make it a point to maintain our marriage daily. We talk to each other, help each other, and reinforce our feelings for each other every day. A job that you enjoy needs the same care and work as a good relationship. I spend a great deal of time thinking about what lessons need to be tweaked and what I can do to improve my class, another opportunity I would have missed had I railed against the unexpected course my life took.