You feel like an adult when
–someone needs to speak up as a voice of reason, and of course you do it
–you have a life-changing decision to make for yourself, you realize how important it is, there is no one else to make it for you, and you take it for granted that you will make it for yourself
–someone else is dependent on you to be responsible for them, and you just do it
–a decision needs to be made for a group, you are the one to make it, and you just do it without freaking out about it
–you are put in charge of something important and no one assumes you need to be directly supervised, including you
–someone who does not know you refers to you as a “man” or a “woman” or calls you “sir” or “ma’am” when you’ve always been referred to as a “boy” or a “girl” or “Dude” or “Miss” or something similar
–fun is something you arrange more for others and less for yourself
(Obviously I think that while feeling like an adult is sometimes something that happens suddenly, it is often a comfort with responsibility and competence that you realize you have matured into gradually. You might feel like a kid masquerading as an adult when you start to buy your own house, but then just like an adult when you’ve made the transaction and you realize you are totally competent to do it in the future.)
You might feel like a kid again (and not in a good way) when
–you don’t feel up to the responsibilities placed on you
–you aren’t trusted to do your job without someone watching you every minute to be sure you get it right
–someone else starts making your decisions for you or you are otherwise stripped of decision-making or excluded from decision-making
–you realize you reacted when you ought to have responded
–your emotions go on a roller-coaster and you don’t know why
–you ought to have been responsible, but you took the easy way, instead
–you want to take care of yourself or someone else, but you can’t
–it is assumed that you aren’t capable of caring for yourself, acting reasonably without being forced to do it, or doing what needs to be done without being nagged about it
(Sometimes, it just takes practice at stepping up to the plate, doing your job, and taking both the successes and the failures to get past this, but sometimes you have to stick up for yourself. Sometimes, too, you have to realize that not even adults are infinitely independent.)
You feel like a kid (in a good way) when
–you could have played it safe and been “reasonable,” but you do what is joyful, imaginative, or generous, instead
–you trust your own sense of spontaneity instead of “going by the book”
–some responsibility is taken off of your shoulders that you once took care of but thankfully and rightfully do not have any more
–you want someone to take care of you, and they do
–you fall in love, you don’t have control of your emotions, and you like it
–you can make friends and enjoy them without overthinking it
–you do the right thing only because you want to, and not because some rule from somewhere else tells you that you ought to
(I also think that “acting like an adult” can be taken too far, to everyone’s detriment.)
Clarification: I don’t think that all of this is what it **means to be an adult. I just think these are the things that typically make us feel **as if we are more or less of an adult.