They may have the bodies of demigods, but they can also have the emotional maturity of a walnut. Show her how even-headed you are and how readily able you are to talk about your feelings in a calm and responsive manner.
If he lasts more than the time it takes to cook an egg in his selfish efforts to reach a boiling point, then the woman can count herself lucky.
Of course however like all fantasies, the reality is often very different from what you imagined, and while there are some very obvious strong points for dating younger women, there are also some downsides and difficulties.
Knowing some of these ahead of time can help you to avoid getting into trouble in your relationship and help you to get the most from the circumstances. Try not to be too possessive: Your girlfriend is likely to get a lot more looks and glances than she would if she was your age and in this sense you are at a definite disadvantage.
Sadly, this is something that younger guys are really bad at.
They will prattle on about themselves incessantly, until the woman they admire is ready to jump out of the nearest window in a last-ditch effort to escape.