'My in-laws are obsessed with me'-- it's a bit slow but he's really in love with her, worries about her and is supportive of her.
'A step mothers marchen'-- ml is reallly in love with our mc and it's shown through his actions too
'Death is the only ending for villainess'-- i feel like this might match the trope too since ml seems so fond of fl and is pretty heartbroken when she's hurt.
'How to get my husband on my side'-- this absolutely fits the description, the way he is sooo in love and helps her heal, i love them sm.
The Broken Ring : This Marriage Will Fail Anyway
https://www.mangago.zone/read-manga/the_broken_ring_this_marriage_will_fail_anyway/
ml who is completely smitten with fl?