Lemme camp here I wanna know tooヾ(☆▽☆)
that's really rare tho.......so Imma camp right here!
I can only remember God of pain's groom that has this kinda plot but that's shounenai
https://www.mangago.zone/read-manga/glasses_cloth_and_playlist/
The uke did get cheated on and found a better man but it kinda revolves more on the rivals to lovers aspect.
I want to know too :3
This suit with your description
https://www.mangago.zone/read-manga/tonari_no_usotsuki_suzaka_shina/
And this list is where uke/seme move on to new lovers not particularly cheaters, most stories are failed unrequited love or abusive relationships ex bf
https://www.mangago.zone/home/mangalist/1295585/
Recommend some yaoi where the uke gets cheated on and he finds himself a better man
Bonus points if the better man is a best friend/person who has had a crush on uke for the longest time/someone trying to get revenge on the cheater in any shape or form