I’m ashamed to say this, becuase its a real sad note, as to where we have fallen to, but under the circumstances, maybe this would work:
Instead of waiting for him to ask you, ask HIM. Think about it: he is deathly afraid of the responsibility getting married entails, and while he will most likely be ok once he grows up (say, 2-3 years after the wedding), right now, he’s just a child.
If he has the potential to be someone, take the initiative, and ask him to marry you.
Whats the worst that can happen…He’ll say no? You’re heading for a no in any case.
And he might just say yes!