sooooo let me get this straight here. you told her you don't want a plutonic relationship nor a serious relationship. is that right? what is it exactly that you want from her? cuz what i get out of the whole thing is that you want a romp in the hay with her and that is it. that's the way i would take it if i were her.
also, why did you break up with her in the first place? was it because she was overweight and you were sick of it? just curious because you seem to mention her being overweight when you two were in a serious relationship and now that she is of average weight you feel she is shunning you.
i'm not sure what to tell you at this point except to maybe just move on with your life and forget about this girl........it sounds to me like she's already got a few issues of her own doing that need to be dealt with. the best thing you could do for her is to be there AS A FRIEND to talk to her when she calls.