Tell the Doctor to get bent.
Telling you to not lift weights and eat 1,200 calories a day is fairly crap.
Females need around 1,800 a day, for sedentary people. More for exercise. Around 200-300 more as a reasonable minimum and depending on intensity you might need more still. If you were marathon training I'd suggest about 800-1,000 a day more than the sedentary average.
A doctor saying weightlifting makes you look bulky is crap. Yes if the female eats 4,000+ calories a day, lifts heavy and does Steroids, tehy may appear nulky but most "naturals" don't look bulky and when have you sen female middle distance runners and swimmers look bulky and if an female olympic swimmer didn't lift and looked like Hilton, they'd probably take 2-3 times longer, just to complete a length.
An extra lb of muscle burns around 45-50 additional calories. If you eat 1,200 calories a day you could increase the risk of mild deficiencies and inadequate intake of things like Calcium, Magnesium, Vitamin K2, Vitamin D, phosphorus etc etc and increase Osteopenia, (thinning bones), risk, maybe even Osteoperosis risk and then potentially increase fracture risk if you did weightlifting too.
Though I should stress the weightlifting comment was in relation to low calories not adequate. Keep the lifting in there
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The 1,200 calories a day could also cause a "starvation mode", where the body clings onto Fat and if you lose muscle from inadequate intake of Protein and one or two other things, you could reduce metabolism, making fat gain a potential possibility instead.
Oh and consider getting another Doctor. Any Doctor telling a female to eat 2/3 of RDA calories and not lift weights, should potentially be struck off.
RDA's for things, are after all intake limits considered acceptable, not generous.
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