How can I help my cat deal with what appears to be separation anxiety?

As many of you know my cat was “missing” for 3 months. He is home, he is skin and bones, the vet said the priority was to get him fed because he is clearly starved. He gave him some medicine, but otherwise he looks reasonably healthy. He recognizes the house, the family, he recognizes the other cats. (They don’t recognize him, but he doesn’t seem to care when they hiss.)

He has been meowing a lot. It seems to stop when he notices that I’m close or when he is able to touch me. I think he has separation anxiety. In fact, as I type this he just dragged a piece of chicken from the kitchen into this room so that he could eat it next to my foot. He was never much of a lap cat, always kind of skittish, but he slept next to me all night, and would meow if I rolled away from him in my sleep.

I don’t want the meowing to become a long term behavior, it is really persistent… and it would get annoying really fast. I just don’t know how to make him feel secure without encouraging the meowing. Are there cat psychologists out there? I seriously don’t know what to do for him, and the poor guy has been through enough, he is obviously traumatized.