I think after all my years of posting here and previously elsewhere on EP sites, your son being the one exhibiting such extreme jealousy, in relation to his mother becoming close to others in his life, including his own child, is the first case I've come across Onward.
I honestly don't think that whether or not you spoiled him, I mean who hasn't spoiled their children from time to time, has anything to do with it.
IMO when it comes to sabotaging relationships it's insecurity, but why and where that comes from when their childhood has been loving, caring and supportive, who can say.
Jealousy isn't known as 'the green eyed monster' for nothing. It's an incredibly destructive emotion, so often destroying the very thing(s) it craves.
The problem with jealousy is that it knows no boundaries. Jealousy of your wife/husband's relationship with family and friends. Jealousy of your child(ren) being close to anyone other than you. Their other parent, GP, extended family members and when they're old enough their GF's/BF's.
This is my biggest fear for our GC, their mother's jealousy, especially as our ES, their father appears to have no back bone when it comes to doing the right thing.
Hope you're feeling a little better DSL. Make sure you take it easy
x.
You haven't created a monster. You are not responsible for his behaviour and the decisions he makes as an adult; he is.