It seems to increase with age. It comes as quite a shock if you're used to getting with pretty much every guy you ever wanted. I don't know which might be worse, having lived most of life not getting rejected and then having to deal with it, or having always been rejected and building up an immunity to it.
I rarely if ever got rejected when I was younger, well, at least not sexually, you know, that part that counts. Seriously very few times and I watched those that did: each time the guy went home to bump fugly. No offense. I figured some sort of fetish or he just wanted to be the pretty one. That happened a few times.
Other than that I didn't really know rejection until I was into my mid and now late 50s. Even early 50s wasn't a problem but by then I was dealing with so much death that maybe I just didn't notice if someone had rejected me. It seemed my life was rejecting me.
I'm starting to get used to it but I don't like it one bit. And I think I'm in a bit of denial about it because if someone doesn't want to have sex with me, I don't take it as rejection; I just think they're being rude.