Beauty is truly in the eye of the beholder, as is so often proclaimed, however I do believe there are popular standards of beauty that everyone can agree with. That being said, I tend to view all of my friends as beautiful- perhaps I've subconsciously chosen them because they are beautiful. I would venture to say that I prefer to surround myself with beautiful women, as opposed to "less beautiful women" than myself. I like to have something to strive for.
Each of my girlfriends has something to offer, to make me feel the friendship is worth while. In each of my friends I find admirable qualities that make me strive to be a better person, more intellectual, more successful, or thinner, have a better complexion, look younger, create a better style for myself. I strongly believe, much like in business, you need to surround yourself with the women you idealize in order to have any chance of reaching that ideal for yoursellf.
I take pride in having beautiful friends. I envy and admire them- without internalizing any of these feelings to feel inadequate. I would much rather enter a bar with beautiful friends in my company, feeling like I'm with the cool crowd, as opposed to walking in with a bunch of wallflowers that no one notices- and there is nothing wrong with being a wall flower, I'm just using your example in answer number 2.
My best advice would be: don't be afraid to strive for more. Find someone who has a quality that you admire, be it physical or intellectual, and befriend her, learn from her, appreciate her, and let her guide you to greater self appreciation. Jealousy, envy, hate- these are simply emotions your ego lets interfere with personal growth!