What I have learned in my life is that you can learn something from every single individual you ever come across. They could be the most ignorant, evil and manipulative person but still teach you a valuable life lesson. Whether that lesson is to always maintain a humble level of self-love and respect or that people just suck, it’s still a valuable lesson. But even bad experiences with people that you love (family, friends, significant others,) can be enriching. The best thing to do when you have a bad experience is to accept that it happened. Whether that be a fight or an awkward period of time where the “romance” just seems dead, accept it for what it was. There is no going back.
Thinking about what you could have done to avoid it or stronger arguments you could have made to make yourself look more right is pointless. It already happened, and that needs to be accepted. Like the expression, build a bridge and get over it. The most valuable thing to do after a bad experience is to reflect upon it with an attitude of non-judgment and assess what you could learn from it. For example, let’s say you have a fight with your significant other about how to spend your Saturday night. He/She suggests going to the movie theater but you’d rather go dancing at the club. They accuse you of never wanting to do what they want to do and you accuse them of being antisocial. This turns into a screaming match that leaves both of you spending Saturday alone.
You have two choices. Let this affect you or don’t. Think about every possible way you could have avoided it: what may happen next, how your relationship may be on the rocks, how angry they are at you, how you have a right to be angry at them and how things should be perfect between you right now. That last one is the biggest error. No relationship can ever be perfect. No two people--no matter how similar--are going to get along all the time. There will always be bad experiences, fights and horrible feelings, and we need these in order to grow. If they didn’t happen we would never learn anything about how to coexist with others and how to improve ourselves. From this particular example maybe one can learn to be okay with doing something they didn’t plan on in the first place, or to not fight fire with fire. Just because someone responds with an accusation you may not like doesn’t mean you have to throw one back at them. Maybe you learn that you would be happier if you just said nothing, and there it is: you just gained something from a bad experience.
So really, is there even a such thing as a bad experience? “Bad” is just a label, and it is just an opinion. Some experiences may not be what you wanted them to be, they just are. They're not good or bad, they just exist. Chances are, a lesson also exists somewhere in them.