Maybe not the norm but they did exist...
I was 19 in 1989 and moved in with my 34 yo boyfriend..
2 years later we split up and I had a brief dalliance with - shock horror - a 42yo!
Then I met someone only 10 years older (much to my family's relief) and we were together for 15years.
I did buck that trend and then went out with someone 10 years younger 🤣
Then someone 6 years younger
Well I was in my 30s by then and full on mid life crisis 😎
I settled down in my late 40s with someone the exact same school year as me and he is the best thing ever 😍