How long is a piece of string?
Your success or failure in GA will depend on two things.........1/ Your desire to achieve your goal at any cost( and I don't mean just dollars,...although you'll need that) and ..2/ A lucky break or three will be neccessary. If you get this, then the way to make a living out of GA is to get OUT of it and go into the airlines.
After seven years (6 in GA) I am yet to meet a GA pilot who has
1/ made an acceptable sustainable standard of living.
2/Managed to keep a partner/ family from the beginning.
3/Saved enough money to buy better than a 1978 toyota corolla.
Sounds a bit gloomy I know, but, thats the rule rather than the exception.
A few good jobs exist in GA, however these are probably harder to secure than the elusive first job in the airlines.
Good luck.