searching...I forgot the title

anyone can tell me the title of a manhwa where the FL had a girl bff and 2nd prince fiancee. but her bff and the prince were secretly in relationship, so they decided to poison the FL which leads to her death but she was given another chance to live. when she woke up, she decided to get revenge, slowly and I think the bff helped the FL to catch the prince aka mastermind...
btw, the bff made the FL eat a lot of sweets and she gained so much weight. I think the FL's pair here is a duke??

plssss. I've been meaning to continue to read this for a long time now, but I can't ╥﹏╥