I have a client who has severely thinning hair... her whole crown is quite short and thin, almost bald.

Her hair in the sides, back, and bangs is thick and healthy but still not more than a few inches long. I"m trying to come up with a hairpiece I can make that will cover this area so that it can grow out A) without becoming more damaged and B) looking good while growing. My client has trichotillomania, a condition that causes her to compulsively pull her hair out. Therefore we have decided she needs something that will completely cover that area to keep her from getting at it. I think that a wig piece would be the best way, or I've heard about a mesh piece that has some synthetic (or real) hair on it, and then you can pull bits of the natural hair through.
Has anyone experienced this, or does anyone have thoughts/suggestions? I've never made a wig but I am certainly ready to give it a go. Today she's coming over and I'm going to attempt to do a weave or make some clip-in pieces for the area around the thin spot, but I fear that since her hair is so short, it won't last long. My client is feeling hopeless about it as it seems to only get worse.