Our son resents whenever we call his cell phone or email him to see whether or not he returned safely from a "road concert choral trip" from his college. He does not understand that we are not trying to check up on him, only concerned that he returned alright from that location. we love him and care about him, but he does not appreciate our concern, appears like the only thing he wants from us is the financial support. Why does it have to hurt so much to show your young adult that you still care about him and he does not want to extend that same love back to you?
Respect you son. He is trying to grow up. The opposite would be terrible. Be proud of yourself that you have succeeded in making him independent.
In my own family, we work as extra parents for a child every second weekend. This has caused a lot of happiness to our family and the child. Ask the local government social services in your hometown, if you are interested. They can often arrange such things.