I've always been really shy and I made a few close friends in elementary school but then my closest friend who was also shy moved to a different school and from what I heard isn't shy anymore and has a bunch of new friends and I am happy for her but at the same time I am envious because all of my other friends got grew away from me when I got to high-school and we barely talk anymore. I try to talk to them but they ignore me and one told me they don't talk to me because I am socially awkward I am trying to make new friends but it seems like all the friends are taken and I am just being forgotten and the world is moving without me.my only friends right now are my cat and my bird but I still feel very lonely

There shouldn't be any such thing as all the friends are taken when there is no limit to friends. Plus, there are bound to be other shy people just like you, dying for someone like you. The old friends who now feel that you are socially awkward (so what, I say, but hey, I'm older now) are so hung up on acting just the exactly right kind of cool are in a way as insecure and desperate as any teenager trying to fit in. Clothes and hair have to be the same type, music, boys, opinions all have to be the same same same, ugh. It's how teens find an identity as they break away from parents. I watched 'awkward' classmates turn into the most successful and beautiful and happy people later in life - the nerds, the girls whose mothers made then wear frumpy clothes, the late growers, the ones who were so shy they couldn't make small talk. I wasn't shy except for one year, I think it was 7th grade, I blushed beet red anytime anyone so much as looked or spoke to me. Then it just stopped.
If there is a way you could ask that one old friend who was willing to tell you what the others said about you, I would. She was forthright and might give you some clues about what you do - try too hard, seem too eager to be part of the group, when they are all about being blasé? If it's just clothes and hair and weight and looks, I say fine, good riddance, wait for friends who don't care about such things.
And search out those other shy people. They are there.