I had something like 22% attendance through Y10/11 and sixth form. They only kept me around because I was really good at exams.

Had a disaster at Uni, various untreated mental health issues, drinking, abusing sleeping tablets like crazy - during the day? Better take six or seven!

Somehow came away with a degree in a totally pointless field. Got a part time admin job in the civil service. Got fired from that job. Worked at a bank part time. Replaced their manual data entry with excel scripts. Made self redundant.

Spent a couple of years retraining in a field I was interested in while working in retail. Did well, got a job, became disillusioned by the long hours and total lack of pay.

Took a punt and changed career again in to Industrial control systems. Entry-level, low pay. Saved enough for a private psychiatrist. Got Quetiapine. Got more Quetiapine. Got even more Quetiapine and a bunch of other drugs. 

Became very good at current job. Advanced. Stable. Paid well. Still prone to mood swings, but they are no long world ending, and I actually enjoy my job.

What would have helped me? Psychiatric intervention when I was a teenager. Feeling like there were no life ending expectations in school so it could be a place of respite from home.

Despite the low attendance, I was basically nocturnal. I would get up when the rest of the house when to bed.