I am sorry things are unpleasant.
A few things jumped out at me that I found troubling.
"She has family that does not live in the area and she left them right out of college to start a new life elsewhere. That may be the cold part of her emotional status."
"I try to be her mother away from home because she doesn’t seem to have a relationship with her and I think she resents that and is taking away our son.."
Regarding the first, we raise children to become adults. They grow up, they move out, maybe they move away. That doesn't make them cold.
The second... "she resents that and is taking away our son"? He is an adult. He can make up his own mind.
I truly am sorry there is strife. But what you describe as close-knit also has a whiff of control issues. And the type of assessments made might better be in the purview of a professional therapist. This kind of thinking is probably not helping the situation. Have you thought about therapy for trying to deal with your feelings about this?
__________________
Makes me sick to the heart, Oh I feel so tired. And the way the rain comes down hard, that's how I feel inside.
--The Cure