Thing to remember with age gaps, is that most couples, the gap is just a couple of years. It's no accident, because what attracts people together in the first place, might have been that they met at school (so obviously similar year), or out in town (40 year olds don't frequent the same clubs as 22 year olds normally - they have more bloody sense ) etc.
It's also because relationships can be about shared experiences, and that means very similar age. You can't talk about Thatch, Duran Duran, big hairstyles etc with a 20 year old, because she'd be hard pushed to remember anything before dance rave music.

This is why when you look at most average couples, there is a very small age gap.

Then, you have to consider other things. Just as for many people, we are attracted to the same sort of person - for others, then the opposite can attract. I know enough people with big age gaps to know this........and we are talking about both uk people.

There are other instances - sometimes it is cultural - where women prefer older men and will seek this sort of relationship. As many on here will know, this is not unusual with SE asia ladies to want older men.

Sometimes this is the issue of these women just looking for a financial way out of a bad place - the proverbial mail order bride. For this reason, some people have an issue about this. It is a shame that it makes "proper" couples who are together for real love, look bad. It makes some people think he is just some dirty old man with a temper problem who can't get a girlfriend in his own country (unfortunately I know some also fitting this description)

With age gaps, you have to always consider, when one partner is retired, maybe 70, 80, might be incontinent, if the gap is so big, then the other might still be in the prime of life, wanting to go out.
This is why someone once said to work out the maximum normal age gap, to half your age and add 7.
Well even that is arbitary, and although it might be a guide, for others it's a load of rubbish.

What really counts is this

First -that it is an equal relationship and there are no power games. So that means that it isn't some power one over the other - one just wanting a route out of the shanty town for example. I mean - that they are together because that is the man/woman they want to share their life with

Second - that both partners have considered the age gap and what it really means. If it is so big, that there won't be issues later in life as the example I gave.

And really, if both of those simple things are satisfied, then it is no-ones damned business but theirs, and the couple shouldn't give a rats ass what anyone else thinks.

That 45 year old guy walking around with a 20 year old, all the other guys would like to be him tonight, and the other women will be thinking that he must have something special to offer, and will remember that when they go to their potbellied tattoo'd husband tonight, as he's sitting there farting on the sofa.

What matters most is compatibility. The norm is 2 year age difference, but that is irrelevant if it isn't right for the two of you. In the end, it is what the two of you think that really matters