Sadgirl,
I feel your pain. But can I tell you that "skinny" is overrated. I've been skinny, like model skinny, like praying-for-hips skinny, like rejected-by-my-ex-for-being-too-skinny (although I was normal weight). I've also been plump several times in my life. So I know how it feels to be either and how uncomfortable it can be either way. But at the end of the day, I'm still me, regardless of the packaging. Like you, I wish I weren't so shy and overlooked (...and I'm slim . . .but with hips). But timidity can be fixed. We just need to keep working at it.
Remember, you are unique and lovely. If you allow that affirmation to guide your thoughts, it will eventually show on the outside, and genuine folks will value that much more than anything.

For those who are caught up with physical appearance, I dismiss them, don't have time for them, don't want them poisoning my brain (which is already mega fragile) with their shallow thinking.