Happiness is letting go of what you think your life is supposed to look like.
There's no denying that our opinions have a massive impact on how we feel about the things in our lives. Too often, these beliefs are warped so much by society that what you think your life should be like is opposite from what it is — this leads to disappointment, unhappiness, and depression.
You might feel like your life isn't even close to where it's supposed to be and that you've "failed." Still, you have to understand that what you believe your life is supposed to look like results from information from the past and present.
The trouble with putting too much stock into other people's opinions is that they're entirely subjective. Although different people have their views on what you should do with your life, it doesn't mean that they know anything about you.
As much as other people might try to influence you, the person who has the most power over your life is yourself. After all, that's the only person who can create any lasting change in it.
You can't let this philosophy be an excuse not to achieve your goals and pursue your dreams — it's a guilt trip to use against yourself! You shouldn't live in fear of disappointment or unhappiness and pretend like some doctor out there could give you a magic pill for feeling good about your life.
Of course, you can't create a life that's completely void of stress or heartache — we all have to deal with those issues at some point or another.
How you approach these "disappointments" and "failures" determines how you will deal with them and if they'll affect your future self. By not letting history define your future self, you're allowing yourself to be happy and live a more fulfilling life.