What is the ruling on repeatedly viewing pornographic websites, repenting from it, then returning to it, and on speaking to someone about sexual matters, meeting with them, and committing forbidden acts with them? And what is the way to repent from all of that, strengthen faith, and be delivered from this lustful self?

You must repent to Allah with sincere repentance from watching pornographic websites and from this sinful relationship, and cut off all contact with this non-mahram man. If this young man repents and turns back [to Allah], then there is no harm in him proposing to your guardian for marriage to you, for the Messenger of Allah, peace and blessings be upon him, said: "Nothing like marriage is seen for two who love each other." The door to repentance is open, as Allah Almighty said: "Say, 'O My servants who have transgressed against themselves [by sinning], do not despair of the mercy of Allah. Indeed, Allah forgives all sins. Indeed, it is He who is the Forgiving, the Merciful.' And return [in repentance] to your Lord and submit to Him before the punishment comes upon you; then you will not be helped." Among the reasons for loving Allah are knowing His attributes and contemplating His generosity and mercy.