How can I make my fiancé love me more, not see my flaws, and not look at anyone else, taking into account my health condition which limits my marriage prospects?

If the marriage contract has not been concluded, then the suitor is a stranger (non-mahram). It is not permissible to be alone with him, nor to display adornment to him, nor to speak with him except out of necessity. It is obligatory to adhere to the limits of lawful interaction. However, if the contract has been concluded, then he is your husband. Happiness and attaining what is with Allah come through His obedience, not through His disobedience.