I think Mogrim and Doris5000 make very good points above – I’m happy I got’being good’ out of my system earlier rather than later. To be blunt you might want to think about what 10-12 hours of training a week means in the context of your free time as you also go to work, commute etcc.? You also make the comment that you’ll stop in the next 2-4 years – why? Why then in particular?
There’s a really good piece of advice in there. Go and find a coach, so you use your time effectively, especially as you’re getting older, and you’ll start to need to change a bit. Also, go and see a sports psychologist. Get someone who can help you work with your need for selfvalidation via sport, or at least use that mental energy more positively. Don’t bother with more self help books – you’ll only absorb what you want to hear, and disregard the rest