Will my atiel EVER like me?

Hi - I have a 20 year old atiel that I have inherited since my mom ped on. He was around for a lot of my childhood, and when I was little I think I scared him a bit. He did used to let me pet him, though. Anyway, he was very bonded to my mom and I didn't handle him much. Now that he's in my care, I find that he doesn't like me at all. I don't know whether he has forgotten who I am, or if he remembers when I was little that I liked to touch his tail feathers (bad, I know, but I was young). Not only does he no longer let me pet him, but he'll hiss and try to bite me if I try to pick him up from the cage. He will let me pick him up off the floor, but he won't stay on my for very long. He is quite agreeable when I talk or sing to him - he chirps and sings right back. But that's it. He'll talk to me, but he doesn't want me to pet him or hold him. I feed him and talk to him everyday, but it's not making a difference.