20 is an early age to be depressed. He needs to be patient.
He probably knows everyone wants someone who has potential to raise a family (financially, spiritually) and to be able to take their spouse out to public functions.
Your son will probably also meet girls who want to marry rich, have children, and not work. He already knows to avoid them. Thank goodness! I understand his dilemma. But do not be deceived, there are some who appear to be dedicated Catholics, and they too want to marry rich, have children, and not work.
There is no gurantee the type of person he wants to marry will be attending the same parish. The community always welcomes new members!