Hope, there are many adult children here who really don't have the capacity to love. It could be their personality disroder (antisocials and narcissists don't love except themselves) so, yeah, we get used to it. I think my son is a narcissist and he does love me to the extent that he can. More than that, he NEEDS me for HIS needs...emotionally. Every oncversation starts out wtih, "This is what's going on with me...me...me...me..."
So while he loves me, he is totally disinterested in me. His siblings have long dismissed him. This makes me sad, but they can not abide his self-involvement and lack of interest in anyone except himself. I guess it's pretty intolerable. I'm used to it, I guess, and I just radically accept it. It is sad, but we can still make good lives for ourselves. We are not one person...our child. We are separate individuals. We can make good lives for ourselves even when our loved ones will not make good choices. We are not them.