I think a 30lb bike sounds heavy... But beyond that, I can totally understand where the OP is coming from. I'm only 5 feet tall. While I have no problems lugging around 40lb bags of kitty litter, lifting a 30lb (which is only a little under a 1/3 of my body weight...) bike over my head to get it onto the roof rack would be difficult for me.
The question I'd have for the OP is why a hybrid - is it for the upright posture (if yes then a cyclocross bike is out), is it for the sturdiness - and if so why does the bike need to be extra sturdy. Is it just that wide tires make her feel more comfortable and stable? Is all of her riding on pavement or does the bike need to be able to handle gravel/dirt? More info would definitely help in making suggestions.