@Rainbunny
Well we're all allowed to be interested in who we want but I have always avoided big age gap relationships for myself.
My aunt married my uncle who was nearly twenty years older than her. She basically became his caregiver when she was just hitting her fifties. She was vibrant and active and wanted to have adventures which all disappeared due to my uncle's age and ill health. She loved him but she always warned me in no uncertain terms never to marry a much older man.
100% this. ^
I would never EVER go for an older man. Some people say (on here) that just because your husband is 20 years older than you, that makes no difference, because someone isn't going to automatically need a carer when they hit 75!
But the fact is that some people will, and also, if you're only in your mid 50s and still in reasonable health, and wanting to travel and start new ventures, you're hardly going to be getting that when your husband is knocking the door of 80!
Some people on here protest, and insist that their 85 year old mother runs marathons, and cycles 15 miles to work every day (coz they ALWAYS still work at 80-odd on here.) In the real world the vast majority of people over 75 will not be in great health, they WILL need help and care, and they will NOT still be bloody working.
Also, re THIS part of your post;
I remember after I got divorced when I was 31, various older male acquaintances came out of the woodwork asking for dates. I actually found it creepy. That these men in their late forties, They weren't exactly old enough to be my father but ugh!
The interesting thing is that they thought they had a chance with me. It's impressive how highly a completely average man can think about himself. I'm not saying I'm a model or anything close to it but looking back I realise I was looking as good as I've ever looked in my early thirties, I was also in really good shape at that time but these near fifty year old men (and they looked it) thought I'd be interested in them? I can't imagine looking at a thirty year old man as a fifty year old woman and thinking I'd have a chance with him romantically!.
This is the kind of thing I was on about further back in the thread. Middle aged men thinking they have a chance with a woman 15-20 years younger is hilarious. They see themselves as still hot, attractive, and a wow with the women. Not ALL of them, but many of them yeah.
Sorry mate, but unless you're Brad Pitt, or Leonardo DiCaprio, you can jog on... 
Very few women are going to fancy a man a generation older, unless he is RICH.
Also (as I said earlier,) these same middle aged men who think they're so 'hot,' also think that women of their own age group are repugnant.
I have seen waaaaaay more middle aged women who look great for their age, than middle aged men who do. Many of them see themselves as an irresistible lothario, who women 20 years younger will be lusting after. In reality, most middle aged men are chubby, balding, hairy, moany, and boring.
Another thing I have noticed about middle aged men - is that they all think they're funny. Telling awful (often bigoted, racist, or sexist 'jokes'.) I know several men who tell 'jokes' constantly. And the 'jokes' are so awful. Not even remotely funny. Yet these men think they're fucking hilarious, and that they should be a stand-up comedian!
And as you say, you wouldn't get a 50 y.o woman thinking she had a chance with a 30 y.o. man! It's so bizarre!