My ex-husband married a woman 20 years younger. She definitely doesn't want children, so that hasn't been a problem for them. They use to travel together and did a lot of cookouts and swims with her sister and husband who live next door. Now all he wants to do is sit in front of the tv. She gets very frustrated. To make it worse he won't "let" her travel with her friends and doesn't even want her to go out with them locally at night. She actually divorced him a year ago, because as she told him she was tired of being married to a boring, old man. She did the online dating thing, but something happened that freaked her out (she won't tell anyone), so she asked if she could come back to him. They are living together now, but he won't remarry her.
One of my dear friends was around 20 years younger than her husband, but they had a wonderful marriage. It was a 2nd for both of them. They did so much together and traveled the world. I think it can be difficult with that kind of age difference, but it can work if both are on the same page. Doesn't sound like hubby is.