Eventually, this is the desired outcome. It may not be with this particular partner or at exactly this time, but you’re probably hoping that at some point your son will form a lasting relationship – perhaps leading to marriage and maybe children. For this to happen, he has to give priority to his partner and the life they have together rather than to you. That’s how it works.
And he’s not too young. Although today’s college-educated young people tend to get married a little later than young people in some earlier generations did, many of them have formed relationships with the person they will eventually marry by the time they’re 24. My daughter, for example, was 23 when she started dating the man she eventually married.