So the plot is that she is isekai’d as the heroine of a story and the male lead falls for her, but after a while she thinks the male lead only loves her for that reason (iirc she also doesn’t even love him back and might’ve even loved someone else). She was reincarnated again but as someone else this time and it didn’t wok out because of ML, and now she’s reincarnated again as another different woman and is determined to get away from the ML. She has the advantage because she went back before he even met the heroine, iirc. But the twist is that ML still remembers her and is looking for her, aware that she has become someone else.
The story has color. Woman is a saintess or something who can make lights I think? She has white hair. Suddenly she is in the body of a random guy and she lives as him for a while and in the process falls in love with his best friend. His friend can sometimes see the real her, I think. And I think she can sometimes see the guy whose body she switched with in her sleep.
Spoilers:
The guy she becomes is actually her long lost twin brother. Their parents were killed and she was taken to become the saintess. They drain the saintesses powers to use as a source of energy and make money. The guy who works with saintesses has helped many times but he fell in love with her and cast the spell to make her appear in her twin brother’s body so that he could save her from death.
I stopped reading this a while ago for reasons, but I will say this series has the most accurate portrayal of severe COCD I’ve ever seen. I remember really relating to some parts.