I do it when I'm bored, stressed, anxious, and angry... So when I'm bored, stressed, anxious, or angry, I find something else to do. Play a stupid internet game or whatever. Sometimes it doesn't work, most of the time it does. Sometimes I can't help it - it's an itch that needs scratching. Which is another thing - my scalp. It doesn't itch as such, not like your foot or your leg itches, but it itches to be scratched. Which is another symptom of trich.
If you don't know when or why you do it, make sure that when you notice you're doing it you make a note of how you feel or what's going on, and the date. That way you can keep track of it and identify what's making you want that feeling that comes with hair pulling.
I've not stopped, I don't think I will - not for a long time at least - but it's far less noticeable.
As for turning points... I'd say in year 9 - I always tied my hair back because of it [tied up is harder to pull out], but it got so bad once that when it grew back I had a tuft of hair that wouldn't stay down. I think the ridiculing I got for that, and the excuses I had to make - to keep people from finding out why I had half the hair at the back of my head growing back - made me realise I had a problem. And I'd just got through bullying, I didn't want it to start again, so I controlled it more.
That and my mum threatening to take me to a psychiatrist [it affects my eyelashes in the corner of my eyes, they itch and pulling them out relieves that, that's what she noticed].
But I've never been to the doctors about it either.
Trich sufferers in general don't like talking about it, it's not exactly a conversation starter, and it comes with shame for a few people. Which is probably why few people go to the doctors about it.
But if it gets to the point where it's affecting your day to day life, something needs to be done about it, and if you need support you need to know it's there - whether it's a doctor or a counsellor or just a group of people who have it as well.
Anyway, this thread's just triggered me, I've got that urge, so I'm off to play Mario on my phone...