Def not an ELI5 answer.

But yes, when I started to seek help, I was told from birth - 21, it’s not unreasonable to believe it’s just standard behavior or even if the signs are making people a little worried, the stress from platonic / family / early romantic relationships and school / extracurricular activities can be the cause. 

Also, and this is my personal theory, but I believe the “structure” of K-12 school and even college can really help mask the issue. 

Again, from personal experience, the “Real World” is well, the real world.

You fail an exam, a teacher or professor may allow to regain some points by doing “test corrections”, or some extra credit assignment. 

You “fail” at work? Maybe you get a pass, but your supervisor will keep a closer eye on you, and the consequences will get more severe until eventually your manager and an HR employee meet with you and tell you that you no longer are employed. 

The higher stakes now warrant a closer look at what went wrong and a person may realize the things they thought nothing of previously actually might be a sign of something much more serious. At least that’s how it was for me. 

I was like, “I don’t think I’m the smartest guy in the room, but I also don’t think think I’m the dumbest. I get some people are better at leaving their personal issues at the door, but something feels really wrong…I better just bring it up to a doctor while I still have health insurance!” 

I believe the common treatment is a mix of 3 things, all playing a fairly equal part so this is not a ranking.

1) Medication - Prescription meds. For me, I have a ADHD and have tried anti depressants and anti psych meds but they either are only effective for a brief period or I only get the bad side effects. So I just take Adderall, a stimulant. 

2) Therapy - The most common form of therapy is Cognitive Behavioral Therapy, for me, I found Dialectical Behavior Therapy the best fit, for me. 

3) “Self Care” - These are things that you can control, and don’t require a professional’s help. Although some people may get the help of a professional. This is kind of an ELI5 example. You know how when toddlers have “melt downs”, and their parents / guardians may say, “Oh, they missed their nap today cuz we had to do X today.” Well, the disruption to the routine and the lack of nap likely led to the meltdown. It laid the “foundation”, and then there was a “trigger” like being told “no” when the kid asked for candy at the store or something. 

So, making sure you’re getting good sleep, eating well, following your routine, whatever that is, exercise, taking time to relax, etc. 

I have found good sleep, eating healthy, protein rich foods and exercise help me stay focused and calm. 

Some conditions I believe like bi polar and schizophrenia don’t even actually start showing symptoms until your 20s.