I used to be very thin. I'm 6' as well and I have very broad shoulders. My older sisters were tall but not as tall as me (5'8" and 5'10"), and both were not broad and had large chests (d+ cup size) while I was an A or B (I still am naturally, I just gained a lot of weight so I gained boobage along with it for now) which looked flat because I was so big boned. People would make fun of my height and my body shape all the time. It was really mean and I was so embarrassed because there was nothing "feminine" about me. The rest of my family all had cute curved pug noses whereas I had a more pointed nose that has bumps in it from accidentally being dropped as a baby (lol). I didn't have a tiny face like my sisters did.
But then I started getting scouted by modeling agents a LOT. I'm not mainstream pretty at all, I'm really not. But these people wanted me. It just goes to show you...people see beauty differently. There are always going to be people who are assholes, and people who think you're "ugly". There's always going to be people who think you're gorgeous. No matter what you do or how you look (you could be the prettiest or ugly person in the world), there will always be these people who feel these ways.
If we all looked the same, it would be pretty boring. I started liking my body. Ok... maybe it was considered more "masculine"... so? You can pull off different types of clothing and look really edgy. Some dresses IMO look better without curves. I don't think there are requirements to look good in any type of clothes though.
Your body may be different, but that doesn't mean it is bad. You don't need curves to be pretty, just be yourself :) I know that's cliche, but it's true!
I know how you feel, I really do. It's not something that you just "get over" feeling. But if you try to think positive thoughts about your body, and remember the people who are commenting are just insecure assholes, you will probably start feeling better over time. I used to be on many different medicines that would either make my weight go down rapidly or up rapidly, and it was so frustrating. People would think I had an eating disorder and think it was ok to just comment on when they barely knew me and it was none of their business -_-