Firstly I wish everyone the best of luck finding that first job. I have been rather lucky and landed my first airline job very soon after finishing training. I'm in my early 20's and although I had to dish out the money for a TR, I am getting paid a lot more than most of my friends do.
People are always comparing flying to becoming a Dr/Lawyer/engineer etc, but there is no way I would ever trade it for that, even if the money is better !
To put the training costs in perspective, a good friend of mine has just spent 50,000GBP for a masters degree.
Hang in there everyone, it can happen ! I've seen it.
Will I be happy in 15 years ? no idea !