Does not feeling guilt after repeated transgressions in the relationship with the fiancé indicate Allah's wrath and the questioner's expulsion from His mercy, and how can she restore her sense of guilt and Allah's رضا (pleasure)?

The relationship with a non-mahram man is sinful, and one must repent from it immediately. Sins gradually blind the heart until evil appears good to it. Allah Almighty says: "Is he then, to whom the evil of his conduct is made fair-seeming, so he deems it good? Verily, Allah leaves to stray whom He wills, and guides whom He wills. So, let not your soul perish in sorrow for them. Truly, Allah is the All-Knower of what they do." Moreover, sins leave a black spot on the heart until it becomes completely dark, neither recognizing good nor denouncing evil. If the servant repents and seeks forgiveness, their heart is polished. But if they return to sin, the blackness increases until it becomes a "rain" (rust), as Allah Almighty says: "Nay! But on their hearts is the 'Ran' (rust) which they used to earn." A bad deed brings blackness to the face, darkness to the heart, weakness to the body, a decrease in provision, and hatred in the hearts of people. As for knowing Allah's anger, that is from the unseen. This blameworthy love affects a servant's love for their Lord, so follow the guidelines for treating infatuation.