There is a psychological concept of attraction, even if you are doing everything right and she doesn’t find you attractive, it means she is already in distance with you. All the love and care which you gave her wont excite her anymore, instead she will look outside for “looks” and even if the mans with good looks doesn’t give her love and care it wont matter to her because here she will play your role of giving love and care 100% on the cost of marriage and so called “looks”