How does a person deal with their homosexual inclinations, while supplicating to God for steadfastness, feeling that marriage is not a solution, and desiring not to mix with men or women?

Homosexuality is a sin and a transgression against Allah and His Messenger; it goes against the natural disposition (fitra) and is a forbidden lust. The solution for a perversion of the fitra and following lust is not suicide or isolation, but rather through fearing Allah Almighty, seeking help from a trustworthy Muslim psychiatrist, and consistently engaging in the remembrance of Allah, lowering the gaze, and fasting.