Responses
I wanna say " for my derelict favorite.. IT DOES HAVE TRAITOR BEST FRIEND but not in the way your thinking.. I think they do it really well.
https://www.mangago.zone/read-manga/for_my_abandoned_love/
This is probably asking too much, but are there any GOOD straight love manhwas, that are also period romances but don't involve a fake daughter, bitchy sister, traitor best friend or A-hole husband? Whether it's a reincarnation/regression or not doesn't matter at all, as long as it happens in a nobility setting and doesn't have a martyred FMC
"Marriage of convenience" kinda fits the bill and I loved it but something lighter would be even better.( Think Jane Austin mood)