Refer back to ECJ's comments - cant think of better advice. Airline employment after your training would be very difficult to achieve and you would be very lucky to achieve it. I have seen the odd chap get through the door aged over 50 but this is an exception. Do not under any circumstances give up your main job. If you want to make a go of it build up the hours and take everything a step at a time.
I've flown with a lot of people who are carreer changers working at the "bottom end" of the airline industry (night freight) and truthfully they admit that the job is really not as good as they thought it would be - infact they would consider going back to their old employment for the money!
However if you dont have a go you will never know and will always critisize yourself - thats the dilemma!
Good luck but dont give up the day job!!!!!!!!!