Holding one's head up and standing correctly, you may or may not see your collarbones, no bones should be prominent so you "notice" them above other things. But I imagine if you're "slumped" and shoulder's rounded and forward, that would make them less prominent.

Yes, you're a wonderful weight. I wouldn't worry about your weight too much at the moment, I'd work on your self esteem and seeing if you can't get back the feeling of being beautiful if you had that before; there is no "real" beauty, it's in the eye of the beholder and if you enjoy yourself inside you're going to enjoy how you look (outsides).