As a parent you always want to see your child happy. Many never stop fighting their battles for them or getting involved in their personal lives.
However there has to come a time when you allow them to learn from their mistakes. Clearly he ignored some "red flags" or maybe he was too self-centered to recognize they were growing apart in the relationship or just RELAXED too much.
Just because you get the job doesn't mean others aren't sending in their resumes. Companies are always evaluating employees. There is no "neutral" in relationships. You're either "growing together" or "growing apart". Communication is the GPS that lets you know which one it is. However in long-term relationships people stop talking about their wants and needs. They just make assumptions each other is happy when in reality it may not be true.
You mention he is (handsome) but like everyone else beautiful people get their hearts broken too! All you can do is "be there" to support him in his time of grief and remind him that his life is not over. A broken heart is often a rite of passage into adulthood.
Ideally we learn to become "better shoppers" in the future.
After all we live on a planet that has over 7 Billion people on it!
Odds are in everyone's favor that there are more than a few of them who would make ideal mates for each of us!
Truth be told when it comes to love and relationships most of us (fail our way) to success. Very few people hit a homerun their first, second, or third time up at bat. If this were not the case we'd all be married to our high school sweethearts!
Sometimes you win and sometimes you learn.
Eventually he'll meet someone where the love is mutual and they'll get married. Silently he will be thanking his (ex) for leaving him because if she hadn't he would not have met this new wonderful woman! It's the circle of life.
Every ending is a new beginning!