Warning, huge amounts of whining ahead.

I'm almost 30 and going through a huge third-life crisis now. I don't have a lot of older friends and would love some suggestions, or hell, some people to complain with me about this.

Okay, first off, the whining. I've just started noticing big changes to my body this year and it blows. My skin is not as clear, my jawline not as pronounced, more wrinkles on my face and neck. I'm still in good shape from working out, but I've noticed my thighs and ass and stomach and knees are all sagging more than before. I know I'm not saying anything revolutionary here, but it makes me feel so helpless. Also, I'm seeing a guy 5 years younger than me, and it's great, but it's also making me feel insecure because he's so young and smooth and hot still.

I thought I'd mostly escaped the curse of being female in a patriarchy, where you judge your own worth by your fuckability, but turns out I haven't really, or why else would I be so sad about it? I haven't found anyone yet, and I'm getting scared that as I get older, men won't be interested in me when they could just date younger women.

Then there's the worst part, the existential life angst. I feel like I haven't really accomplished anything, that I've wasted my 20s and now it's too late to really do anything important or noteworthy. I want to change something or do something worthwhile, but I don't know how. I'm scared at the thought that my life is just going to be this big slide into mediocrity.

Anyone else feel this way, or better, felt this way in the past and overcame it?