He saved up, got his own place and has been doing quite well. A life he never would have had if he'd hung on to the old job.
It always amazes me that people will hang onto a crap situation forever just because it's the "easy" thing to do. A lousy job, a house they can't afford, a kid in their house on drugs (all of the above for my brother), or as we often see here, a relationship with someone who no longer loves them or even cares about them. Glad your son was able to break out of that rut and make a better life. Often when people finally do end that lousy relationship or move out of that expensive home or quit that messed up job, they look back and are astonished they didn't do it sooner. Things can get better very quickly when we finally let go.