Have you gone for counselling, Guy? You need some. I'm quite serious. And I'm not making fun of you, a good counsellor can really help you figure out your issues.
You are NOT the only person to overcome a shitty childhood/adolescence and go on to make something of themselves. In fact, many very successful ppl did well BECAUSE they learned how to endure and overcome hardship.
I hope you do this, heal, learn and become something. Go.
Second thoughts can generally be amended with judicious action; injudicious actions can seldom be recovered with second thoughts.
--Cyteen by C.J.Cherryh