My heart breaks for you, as I know I would be shattered to be pushed away from either of my boys.
However, I have learned two very valuable lessons in life. One is: If you feel as if you are in a relationship and you are the one doing all the "rowing" (as in a row boat), stop rowing. Sometimes the other person is so used to you putting in all the effort they take you for granted and may look at you differently if you start to care for yourself more and them less.
The other thing I have learned in life is: You teach people how to treat you. When I am unhappy in any relationship, I look back at how I react to their actions and most of the time, there is something i can change about myself that changes the dynamic.
That said, it is terribly hard when it is one of your children and I have spent the better part of this year trying to figure out what I can and cannot change and learning to live with things that I cannot change. The Serenity Prayer in action.