Did you like the way you looked, OP? Personally, I think full boobs and cinched in waist is really attractive. You said you knew that if you bought them, people would stare when you’re wearing them. This sounds to me like it was less a case of not liking the dresses on yourself, but more the case of being concerned with others’ reactions.
No two ways about it, it’s really uncomfortable being stared at, but at the same time, why should others get to dictate your choices? If you liked the dresses on yourself, my advice would be to try not to internalise their reactions. It’s their problem that they can’t handle seeing a full bust. They’re the ones with issues. Hold your head up high and be proud and confident in your own skin. As long as you allow other’s perceptions dictate your choices, you’re not making your own choices. So start making choices for you. The more you do it, the less you find that you’re bothered by their reactions, because making your own choices, for you, and you alone, is empowering, and when we’re empowered, we’re strong.
My advice regarding staring is that, if you feel safe to do so, stare right back at them. It usually takes them by surprise and they stop staring pretty quickly. If you find it difficult to maintain eye contact, look at them in the spot between their eyebrows. It looks like you’re looking directly at them, even though you’re not. It’s a clever hack.