The first thing to learn is that you really are making the choices in your life--even the ones you blame on others. You are in control of your own mind. Even total passivity is the constant deciding it would be better not to act.
The second thing to learn is that your mind is in control of your experience. You are not really being swept along by a malicious or uncaring world. Your relationships do not simply blow up of their own accord. Much of what seems to have gone wrong "all by itself" is the result of a psychological lazyiness, a tendency to take the emotionally easy way out ( which can look like doing it the hard way to others who observe your behavior). Avoiding little confrontations, making excuses, hedging your committments...it all adds up to trouble.