Don't put the opinions of a generalized "other" first, that's true. But listen to the opinions of those you respect, and re-examine often if the people you choose to respect are the right people for the job. If one of those people were to die today, would people come to their funeral simply to be seen at the funeral of someone well-known or high up in some hierarchy... or would they come to that funeral to talk about their wisdom, their quiet contributions to society, the way they made time for others, rarely complained, worked with their hands, or welcomed everyone and anyone into their home?
As I grow older, I find individuality, and my desperate greedy scrabbling for it, to have been over-rated. The cult of The Individual (which does have intellectually interesting roots) offers merely linear rewards. (Perhaps I was not Individual enough?) But somehow, doing things for others, noticing others (really noticing, as in quieting your own thoughts in order to reframe your mind to imagine being another person) as part of everyday life, caring for people who may have no opportunity to return that care in the future -- there is just something exponentially more satisfying about it, though perhaps only when you are choosing it for yourself. Perhaps it is because I don't worry so much about my identity -- without my sense of self at risk, I'm much more free to choose to do what I want, and increasingly I do not choose the things and people that promise "happiness". (Which is not entirely subjective, but can be broken down into components that may matter more or less to you.)
That said, it takes bitter experience to recover from giving to toxic souls. Some people stay bitter the rest of their lives. I have to fight that same bitterness. Its value on the Internet as "life experience street cred" is not worth the harm of holding on to it.
(Do you know that giving gifts is a form of asserting power and reinforcing hierarchy? So you must also think on what it means to give to people, what is given, what is really received in return.)
Being a grownup sucks, sometimes, even often. I say it a lot, jokingly. But even as I say it, the truth, that is mine and mine alone, is that I am free. So free. So lucky! Everywhere that I look, I find a person on whom I can bestow a smile or ask about their day or do a little extra work for.
You just have to find your own answer, but usually when you do, it turns out it was blindingly obvious all along.